Wednesday, January 9, 2008

7th Grade- Chapter 1 Online Review

7th Grade - Chapter 1 ONLINE REVIEW

True/False
Indicate whether the statement is true or false.

____ 1. Science has been used throughout history to answer questions about the world.

____ 2. Using a computer graphic is the only effective way to display the data from an experiment.

____ 3. If the results of your experiment do not support your hypothesis, it means that your hypothesis was wrong.

____ 4. Scientific discoveries have been made by people of different races, sexes, cultures, and time periods.

____ 5. There is usually only one correct method that can be used to solve a problem.

____ 6. The number of trials conducted is the same in every experiment.

____ 7. If the results of experiments do not support a prediction, scientists change their predictions.

____ 8. Because the quality of the solution to a problem depends on how well the entire project is carried out, planning is a very important step in science.

____ 9. Although a model was useful for locating the source of an 1871 cholera epidemic, models are rarely useful to scientists trying to solve other problems.

____ 10. Good experiments can only be conducted if you have the latest materials and tools.

____ 11. Modern electronic communications allow people throughout the world to learn quickly about new discoveries.

____ 12. A hypothesis is a statement of fact.

____ 13. Scientific discoveries are made only by professional scientists.

____ 14. Scientific discoveries influence only areas related to our health.

____ 15. Any information gathered from the Internet can be assumed to be accurate.

____ 16. The more trials you can run in an experiment, the more reliable the results.

Multiple Choice
Identify the choice that best completes the statement or answers the question.

____ 17. What is the name for the steps scientists go through to solve problems?
a.
drawing conclusions
b.
forming a hypothesis
c.
research design
d.
scientific method


____ 18. Rita wants to study the history of her town. What type of research will she have to do?
a.
descriptive research
b.
experimental research
c.
research design
d.
variable research


____ 19. Why is a microscope considered technology?
a.
It uses electricity and has lenses.
b.
It uses a technique that helps solve a problem.
c.
Some people use it every day.
d.
It enables people to see details inside cells.


____ 20. How might a scientist show bias in an experiment?
a.
by asking others to verify the data
b.
by choosing a random sample by computer
c.
by drawing conclusions without analyzing data
d.
by using multiple trials to confirm data


____ 21. Mike is testing the effects of friction on a toy car going down a ramp. He runs one trial with sandpaper on the ramp and another trial with cloth on the ramp. What else does he need in his experiment?
a.
a control group
b.
a longer ramp
c.
an independent variable
d.
a technology


____ 22. Margo recorded data for her experiment on a line graph.


What conclusions can she draw from her data?
a.
Growth declined steadily each week.
b.
Growth increased steadily each week.
c.
A growth pattern cannot be determined.
d.
Growth will probably stop soon.


____ 23. What happens after a technological design process is tested successfully?
a.
Design flaws are identified.
b.
The new process is tested with the public.
c.
The constraints are listed.
d.
A pilot plant can be built.


____ 24. Which of the following is NOT a step in the scientific method?
a.
analyze your data
b.
communicate your results
c.
find your biases
d.
test your hypothesis


____ 25. Mike is conducting an experiment to see if his dog will eat a new brand of dog food. He will replace the dog’s old food with the new brand. Identify the dependent variable in this experiment.
a.
the amount of food
b.
the place the food is left
c.
the type of food
d.
whether the dog eats


____ 26. Why is it important for scientists to present their findings to the public?
a.
The public has to understand every scientific finding.
b.
Scientific data can benefit society in different ways.
c.
The scientist might be able to get the data published.
d.
The scientist needs credit for his or her findings.


____ 27. What is the best way to predict when the next full moon will occur?
a.
Collect data about the time of the sunset each day.
b.
Design an engineering experiment.
c.
Draw your own conclusion.
d.
Make a model of the solar system.


____ 28. Clara is conducting an experiment to find out the number of times her lab mice received a reward for finishing a task. She is using a tally chart to keep track of each mouse and the number of rewards each receives.


What is the best type of graph for her to use to analyze her data?
a.
bar graph
b.
line graph
c.
pictograph
d.
pie graph


____ 29. How does engineering meet human needs?
a.
It uses newly designed products.
b.
It solves problems.
c.
It uses technology.
d.
It uses science.


____ 30. Scientists use prior experience to ____.
a.
collect data
b.
make predictions about what will happen under certain circumstances
c.
analyze their data
d.
serve as a control in their experiments


____ 31. One example of technology that is commonly used by scientists is ____.
a.
computers
c.
variables
b.
hypotheses
d.
observations


____ 32. Examples of the skills used in science include ____ and ____.
a.
cholera , E. coli outbreaks
c.
facts , inferences
b.
clues , detectives
d.
observations , measurements


____ 33. After scientists analyze the results of their experiments, they ____.
a.
form hypotheses
b.
include a control
c.
communicate those results to other people
d.
choose the variables they want to test


____ 34. Which of the following steps to solve a problem must be completed first?
a.
analyzing data
c.
forming a hypothesis
b.
recognizing and identifying the problem
d.
testing a hypothesis


____ 35. Which of the following steps to solve a problem is completed last?
a.
analyzing data
c.
drawing conclusions
b.
recognizing and identifying the problem
d.
testing a hypothesis


____ 36. Listing what is known about a problem and possible ways to solve the problem are parts of ____.
a.
making a plan
c.
testing a hypothesis
b.
drawing conclusions
d.
eliminating bias


____ 37. ____ can save time and money by testing ideas that would otherwise be difficult to test quickly or easily.
a.
Biases
c.
Models
b.
Conclusions
d.
Variables


____ 38. A prediction or statement that can be tested is ____.
a.
a conclusion
c.
a control
b.
an observation
d.
a hypothesis


____ 39. A factor in an experiment that can change is ____.
a.
an observation
c.
a control
b.
a variable
d.
a hypothesis


____ 40. A sample that is treated exactly like the other experimental groups except that the variable is not applied to it is a(n) ____.
a.
observation
c.
control
b.
variable
d.
hypothesis


____ 41. Scientists conduct multiple trials of their experiments because ____.
a.
their results are more likely to be reliable
b.
it costs less to run more trials than fewer trials
c.
unusual occurrences are likely to be repeated every time
d.
experiments always have the same results


____ 42. One tool that can be used to display your data is a ____.
a.
balance
c.
microscope
b.
spring scale
d.
computer


____ 43. One way to reduce bias in an experiment is to ____.
a.
ask only girls a question about a school topic
b.
take numerical measurements of the results
c.
use descriptive phrases as your data
d.
make sure that the results come out the way you want them


____ 44. A good way to organize and record your results and observations is ____.
a.
in a data table
b.
by using a calculator
c.
with a balance or spring scale
d.
by having a hypothesis before you begin your experiment


____ 45. Which of the following units is part of the International System of Units, or SI?
a.
pounds
c.
meters
b.
ounces
d.
inches


Completion
Complete each statement.

46. use of knowledge to make products or tools ____________________

47. a prediction or statement that can be tested tools ____________________

48. SI is used for this purpose ____________________

49. sample treated like other experimental groups except no variable is used ____________________

50. sample taken without bias ____________________

51. a factor in an experiment that can change ____________________

52. a way or a process to investigate what is happening around us ____________________

53. way to organize and record results and observations ____________________

Correctly complete each sentence by choosing the best choice in parentheses.

54. Scientists use ______________________________ (observations, experiments, observations and experiments) to find answers to questions.

55. In today’s society, there is/are usually ____________________ (only one, a pair of, several) scientist[s] working on a problem at one time.

56. _________________________ (Making a detailed plan, Making a model, Identifying the problem) is the first step a scientist would take to solve a problem.

57. New artifacts, new techniques, and new social-technical systems are types of ____________________ (scientific discovery, technology, engineering advances).

58. The first step in finding a scientific solution to a problem or human need is ____________________ (make a discovery, define a problem, test a model).

Matching

Match each term with its description below.
a.
hypothesis
e.
science
b.
variable
f.
technology
c.
control
g.
globalization
d.
SI



____ 59. use of knowledge to make products or tools that people can use

____ 60. a sample that is treated exactly like the other experimental groups except that the variable is not applied to it

____ 61. worldwide distribution

____ 62. a system of units used by scientists that is based on units of ten

____ 63. a prediction or statement that can be tested

____ 64. a factor in an experiment that can change

____ 65. a process used to solve a problem

Match a or b to each term below.
a.
general skill used in science
b.
specific step scientists follow to solve problems


____ 66. observing

____ 67. analyzing data

____ 68. forming a hypothesis

____ 69. comparing and contrasting

____ 70. classifying

____ 71. drawing conclusions

____ 72. recognizing the problem

____ 73. testing a hypothesis

____ 74. measuring

Match the description with the correct term. Some items may not be used.
a.
model
g.
control
b.
random
h.
scientist
c.
data table
i.
hypothesis
d.
trial
j.
bias
e.
technology
k.
variable
f.
science log
l.
science


____ 75. a way to record results and observations accurately

____ 76. a single run of an experiment

____ 77. the application of science to make products or tools

____ 78. a way or a process to investigate what is happening around us

____ 79. a prediction or statement that can be tested

____ 80. a slanted view

____ 81. a factor that can change in an experiment

____ 82. used to represent things that happen too slowly or quickly t observe directly

____ 83. a type of sample taken without bias

____ 84. sample treated like other experimental groups except no viable is used

Match the following SI units with what they measure.
a.
temperature
d.
length
b.
liquid volume
e.
mass
c.
area



____ 85. meter

____ 86. gram

____ 87. tonne

____ 88. liter

____ 89. degrees Celsius

Short Answer

90.
Why is it important for all scientists to follow the same general steps when doing scientific investigations?

91.
Dana writes a detailed plan for a scientific investigation. First she shows her plan to her lab partner. He advises that she should use only one independent variable instead of two. She then rewrites her plan to incorporate his comments, and she conducts the experiment.

Part A Why do you think Dana’s lab partner advises against two independent variables in her experiment?

Part B If Dana’s lab partner wants to repeat the experiment, how would he do so?

92.
Give at least two reasons why scientists use the International System of Units (SI).

93.
List at least two reasons for designing your data tables before beginning your experiment.

94.
What are two ways that scientists communicate their results to other people?

95.
List three examples of how technology has made entertainment more accessible to people over the last one hundred years.

96.
Describe how scientists around the world use technology to discuss their results.

97.
How is the work of scientists similar to the work of detectives?

98.
Describe how prior knowledge may be used by scientists.

99.
List three ways that computers can be used in research.

100.
List at least four skills that scientists commonly use.

101.
List at least four types of information that scientists might include in a journal.

102.
Sequence the following steps: test your hypothesis, draw conclusions, recognize the problem, analyze the data, form a hypothesis.

103.
How might scientists go about trying to solve a large, complicated problem?

104.
Give an example of how scientists might use a computer model.

105.
List at least two possible sources of information that you could use to form a hypothesis.

106.
List at least three things you should be careful to do when designing an experiment.

107.
What are at least two factors that might influence the decision about how many trials of an experiment to conduct?

108.
State at least one possible source of bias in an experiment and describe how you can reduce it.

109.
If the results of your experiment do not support your hypothesis, have you still learned something important? Explain.

110.
Besides advances in the entertainment industry, give an example of how technology could make a difference in your everyday life.

111.
Are all scientific discoveries made by professional scientists? Explain.

112.
Describe how new scientific knowledge can challenge old ways of thinking or doing things.

113.
Is all scientific information good? Can some information be harmful? Can science make these decisions?

Figure 1-1

114.
An experiment was conducted to test which of two antibiotics was more effective at killing a certain type of bacterium. Cultures A and B were treated with antibiotic 1; cultures C and D were treated with antibiotic 2; culture E was not treated with any antibiotic. Based on the results shown in Figure 1-1, what conclusion would you draw about which antibiotic is more effective? Explain. What is the purpose of culture E?

115. Number these steps for doing an experiment in the correct order.

a. Test your hypothesis.
b. Analyze your data.
c. Recognize the problem.
d. Form a hypothesis.
e. Communicate your results.
f. Draw conclusions.

116. How do new scientific discoveries affect our everyday life? Give examples.

117. What are some ways that data can be recorded in a science journal?

118. How could you use two beakers, distilled water, two hot plates, two thermometers, and salt to test if adding salt affects the boiling point of water?

119. Complete the following events chain for doing experimental research.

1. Recognize the _________________.
¯
2. Form a ______________________.
¯
3. Select dependent and independent
___________________
ç
Run multiple trials of experiment
¯
4. Identify _____________________.
¯
5. ___________________ your results.
¯
6. Draw ______________________.
¯
communicate


120. Compare and contrast science and technology.

121. Choose an object that you use every day. Explain how science and technology were applied to its development.

122. Explain how the Internet or its parts could be described as an artifact, a technique, and as a social-technical system.

123. What are the main steps of solving a scientific problem?

124. Discuss two advantages of using the International System of Units, or SI, for measurements in scientific research.

Essay

125. If an experiment tested two variables at the same time, would the findings of the experiment be reliable? Explain.

126. Give two examples of what could cause scientists to change a hypothesis or theory they have formulated.

127. Can you think of any tools or technologies that might have developed from people’s observations of natural phenomena?

128. Describe a problem that was solved by development of a new technology and the steps of the solution process.
7th Grade - Chapter 1 ONLINE REVIEW
Answer Section

TRUE/FALSE

1. ANS: T PTS: 1 DIF: Webb's II OBJ: 1/1
STA: SC.H.1.3.1 SC.H.1.3.2

2. ANS: F PTS: 1 DIF: Webb's II OBJ: 4/2
STA: SC.H.1.3.3 SC.H.3.3.7

3. ANS: F PTS: 1 DIF: Webb's II OBJ: 3/2
STA: SC.H.1.3.1 SC.H.1.3.5 SC.H.1.3.7

4. ANS: T PTS: 1 DIF: Webb's I OBJ: 6/3
STA: SC.H.1.3.6 SC.H.3.3.5

5. ANS: F PTS: 1 DIF: Webb's I OBJ: 3/2
STA: SC.H.1.3.1 SC.H.1.3.3

6. ANS: F PTS: 1 DIF: Webb's I OBJ: 4/2
STA: SC.H.1.3.3 SC.H.1.3.4 SC.H.1.3.7

7. ANS: T PTS: 1 DIF: Webb's I OBJ: 1/1
STA: SC.H.1.3.1 SC.H.1.3.5 SC.H.1.3.7

8. ANS: T PTS: 1 DIF: Webb's I OBJ: 3/2
STA: SC.H.1.3.4 SC.H.1.3.5

9. ANS: F PTS: 1 DIF: Webb's II OBJ: 3/2
STA: SC.H.1.3.3

10. ANS: F PTS: 1 DIF: Webb's II OBJ: 4/2
STA: SC.H.1.3.3

11. ANS: T PTS: 1 DIF: Webb's I OBJ: 6/3
STA: SC.H.3.3.6 SC.H.3.3.7

12. ANS: F PTS: 1

13. ANS: F PTS: 1

14. ANS: F PTS: 1

15. ANS: F PTS: 1

16. ANS: T PTS: 1

MULTIPLE CHOICE

17. ANS: D PTS: 1 DIF: Webb's I STA: SC.H.1.3.3

18. ANS: A PTS: 1 DIF: Webb's I STA: SC.H.1.3.3

19. ANS: B PTS: 1 DIF: Webb's II STA: SC.H.1.3.3

20. ANS: C PTS: 1 DIF: Webb's I STA: SC.H.1.3.4

21. ANS: A PTS: 1 DIF: Webb's II STA: SC.H.1.3.5

22. ANS: B PTS: 1 DIF: Webb's II STA: SC.H.1.3.4

23. ANS: D PTS: 1 DIF: Webb's I STA: SC.H.1.3.1 SC.H.1.3.2

24. ANS: C PTS: 1 DIF: Webb's I STA: SC.H.1.3.2 SC.H.1.3.4

25. ANS: D PTS: 1 DIF: Webb's II STA: SC.H.1.3.5

26. ANS: B PTS: 1 DIF: Webb's II STA: SC.H.1.3.4

27. ANS: D PTS: 1 DIF: Webb's II STA: SC.H.1.3.2

28. ANS: A PTS: 1 DIF: Webb's II STA: SC.H.1.3.4

29. ANS: B PTS: 1 DIF: Webb's II STA: SC.H.3.3.4

30. ANS: B PTS: 1 DIF: Webb's II OBJ: 1/1
STA: SC.H.1.3.1

31. ANS: A PTS: 1 DIF: Webb's I OBJ: 5/3
STA: SC.H.3.3.7

32. ANS: D PTS: 1 DIF: Webb's I OBJ: 2/1
STA: SC.H.1.3.4

33. ANS: C PTS: 1 DIF: Webb's I OBJ: 2/1
STA: SC.H.1.3.4 SC.H.3.3.6

34. ANS: B PTS: 1 DIF: Webb's I OBJ: 3/2
STA: SC.H.1.3.4

35. ANS: C PTS: 1 DIF: Webb's I OBJ: 3/2
STA: SC.H.1.3.4

36. ANS: A PTS: 1 DIF: Webb's I OBJ: 3/2
STA: SC.H.1.3.4

37. ANS: C PTS: 1 DIF: Webb's I OBJ: 3/2
STA: SC.H.1.3.3

38. ANS: D PTS: 1 DIF: Webb's I OBJ: 3/2

39. ANS: B PTS: 1 DIF: Webb's I OBJ: 3/2
STA: SC.H.1.3.5

40. ANS: C PTS: 1 DIF: Webb's I OBJ: 3/2
STA: SC.H.1.3.5 SC.H.1.3.7

41. ANS: A PTS: 1 DIF: Webb's I OBJ: 4/2
STA: SC.H.1.3.4

42. ANS: D PTS: 1 DIF: Webb's I OBJ: 5/3
STA: SC.H.3.3.7

43. ANS: B PTS: 1 DIF: Webb's I OBJ: 4/2
STA: SC.H.1.3.4

44. ANS: A PTS: 1 DIF: Webb's I OBJ: 4/2
STA: SC.H.1.3.4

45. ANS: C PTS: 1 DIF: Webb's I OBJ: 4/2

COMPLETION

46. ANS: technology

PTS: 1

47. ANS: hypothesis

PTS: 1

48. ANS: measurement

PTS: 1

49. ANS: control

PTS: 1

50. ANS: random sample

PTS: 1

51. ANS: variable

PTS: 1

52. ANS: science

PTS: 1

53. ANS: data table

PTS: 1

54. ANS: observations and experiments

PTS: 1

55. ANS: several

PTS: 1

56. ANS: Identifying the problem

PTS: 1

57. ANS: technology

PTS: 1

58. ANS: define a problem

PTS: 1

MATCHING

59. ANS: F PTS: 1 DIF: Webb's I OBJ: 5/3
STA: SC.H.1.3.3

60. ANS: C PTS: 1 DIF: Webb's I OBJ: 3/2
STA: SC.H.1.3.5

61. ANS: G PTS: 1 DIF: Webb's I OBJ: 6/3
STA: SC.H.3.3.6

62. ANS: D PTS: 1 DIF: Webb's I OBJ: 4/2

63. ANS: A PTS: 1 DIF: Webb's I OBJ: 3/2

64. ANS: B PTS: 1 DIF: Webb's I OBJ: 3/2
STA: SC.H.1.3.5

65. ANS: E PTS: 1 DIF: Webb's I OBJ: 1/1
STA: SC.H.1.3.3

66. ANS: A PTS: 1 DIF: Webb's I OBJ: 2/1
STA: SC.H.1.3.4

67. ANS: B PTS: 1 DIF: Webb's I OBJ: 3/2
STA: SC.H.1.3.4

68. ANS: B PTS: 1 DIF: Webb's I OBJ: 3/2

69. ANS: A PTS: 1 DIF: Webb's I OBJ: 2/1
STA: SC.H.1.3.4

70. ANS: A PTS: 1 DIF: Webb's I OBJ: 2/1

71. ANS: B PTS: 1 DIF: Webb's I OBJ: 3/2

72. ANS: B PTS: 1 DIF: Webb's I OBJ: 3/2

73. ANS: B PTS: 1 DIF: Webb's I OBJ: 3/2
STA: SC.H.1.3.4

74. ANS: A PTS: 1 DIF: Webb's I OBJ: 2/1
STA: SC.H.1.3.4

75. ANS: C PTS: 1

76. ANS: D PTS: 1

77. ANS: E PTS: 1

78. ANS: L PTS: 1

79. ANS: I PTS: 1

80. ANS: J PTS: 1

81. ANS: K PTS: 1

82. ANS: A PTS: 1

83. ANS: B PTS: 1

84. ANS: G PTS: 1

85. ANS: D PTS: 1

86. ANS: E PTS: 1

87. ANS: E PTS: 1

88. ANS: B PTS: 1

89. ANS: A PTS: 1

SHORT ANSWER

90. ANS:
Following the same general steps when designing and conducting experiments helps to form a universal language and method for all scientists around the world to follow. This will help when scientists need to repeat experiments and use data from other scientists’ experiments to conduct their own studies.

PTS: 1 DIF: Webb's II STA: SC.H.1.3.4 SC.H.1.3.6

91. ANS:
Part A Scientific investigations should have only one independent variable so that any data can be attributed to that independent variable. With two variables, it would be difficult to explain the results of the experiment. One variable makes it easy to analyze the data and communicate the results.

Part B Dana’s lab partner would follow the detailed written plan of her experiment. This type of plan allows for other scientists to verify a researcher’s results by repeating the experiment themselves.

PTS: 1 DIF: Webb's III STA: SC.H.1.3.5

92. ANS:
Answers may include: it gives scientists a common language; multiplying and dividing by 10 makes calculations easy to use; prefixes used with units change them to larger or smaller units.

PTS: 1 DIF: Webb's II OBJ: 3/2 STA: SC.H.1.3.4

93. ANS:
Answers may include: the data will be organized from the start; you will save time by not having to rewrite the data in a table; you will know that you have all the data you need to accurately analyze the results of the experiment.

PTS: 1 DIF: Webb's II OBJ: 4/2 STA: SC.H.1.3.4

94. ANS:
written reports and verbal presentations

PTS: 1 DIF: Webb's II OBJ: 3/2 STA: SC.H.3.3.6

95. ANS:
Answers may include: movies on large screens; movies on TV; videotaped movies; DVD movies on computer monitors.

PTS: 1 DIF: Webb's II OBJ: 5/3 STA: SC.H.3.3.7

96. ANS:
They may use cellular phones and computers to contact other scientists.

PTS: 1 DIF: Webb's II OBJ: 6/3 STA: SC.H.3.3.7

97. ANS:
Both have a problem to solve; both look for clues that they use to solve that problem.

PTS: 1 DIF: Webb's II OBJ: 1/1 STA: SC.H.1.3.2 SC.H.1.3.3

98. ANS:
Prior knowledge is used to make predictions about the results of an experiment. These predictions can be stated as the hypothesis.

PTS: 1 DIF: Webb's II OBJ: 1/1

99. ANS:
Answers may include: information about finding useful resources (books, magazines, etc.) can be found; internet links or web pages can be found; data can be analyzed; data can be displayed in graphics.

PTS: 1 DIF: Webb's II OBJ: 2/1 STA: SC.H.3.3.7

100. ANS:
Answers may include: observation, classification, interpretation of data, making measurements, comparing and contrasting.

PTS: 1 DIF: Webb's II OBJ: 2/1 STA: SC.H.1.3.4

101. ANS:
Answers may include: descriptions of their observations, mathematical measurements or formulas, step-by-step descriptions of procedures, listings of materials, drawings of equipment setups, specific results (data), questions that come up during experiments, problems that occur and possible solutions, other observations, etc.

PTS: 1 DIF: Webb's II OBJ: 2/1 STA: SC.H.1.3.3 SC.H.1.3.4

102. ANS:
recognize the problem, form a hypothesis, test your hypothesis, analyze the data, draw conclusions

PTS: 1 DIF: Webb's II OBJ: 3/2 STA: SC.H.1.3.4

103. ANS:
They might break the problem into smaller problems and decide which of those needs to be solved first. Different scientists might work on different aspects of a problem.

PTS: 1 DIF: Webb's II OBJ: 3/2 STA: SC.H.1.3.3

104. ANS:
Answers may include: a map to locate the source of a cholera epidemic; a map of the spread of the spruce beetle; three-dimensional models of microscopic bacterium or a huge asteroid; design safer airplanes or buildings; testing ideas that would be too expensive to test other ways.

PTS: 1 DIF: Webb's II OBJ: 3/2 STA: SC.H.3.3.7

105. ANS:
Answers may include: prior knowledge; science literature at the library; World Wide Web; computer disks or CDs.

PTS: 1 DIF: Webb's II OBJ: 3/2 STA: SC.H.1.3.4 SC.H.1.3.5

106. ANS:
Answers may include: use a control; limit the number of variables being tested; conduct enough trials to get sufficient data; use proper materials and tools; eliminate bias; prepare good data tables.

PTS: 1 DIF: Webb's II OBJ: 4/2 STA: SC.H.1.3.4 SC.H.1.3.5

107. ANS:
time, cost, availability of materials, amount of space to set up trials

PTS: 1 DIF: Webb's II OBJ: 4/2

108. ANS:
different interpretations of verbal descriptors—to avoid this use numerical measurements; biased samples—use random samples

PTS: 1 DIF: Webb's II OBJ: 4/2 STA: SC.H.1.3.4

109. ANS:
Yes, it is just as important to learn that your hypothesis was incorrect as it is to learn that your hypothesis was correct. [There is also the possibility that even though the hypothesis was not supported in one experiment, it might still be correct. This is not actually stated in the text, but it is implied in the discussion of multiple trials and reliability.]

PTS: 1 DIF: Webb's II OBJ: 3/2 STA: SC.H.1.3.2 SC.H.1.3.7

110. ANS:
Answers may include: satellite tracking systems in cars; instruments that doctors can use to operate on unborn children; skin patch to release medicine into a person's system.

PTS: 1 DIF: Webb's II OBJ: 5/3 STA: SC.H.3.3.7

111. ANS:
No. Discoveries can be made by almost anyone—young or old, people pursuing a hobby, people of different sexes, races, cultures, etc.

PTS: 1 DIF: Webb's II OBJ: 6/3 STA: SC.H.1.3.6 SC.H.3.3.5

112. ANS:
New information can show that the old way of thinking or doing things is incorrect. For example, new discoveries may not fit in a current classification scheme. New models or new methods for doing things can be created to fit the current information. These new ways are also subject to change based on possible future discoveries.

PTS: 1 DIF: Webb's II OBJ: 5/3 STA: SC.H.1.3.1 SC.H.1.3.2

113. ANS:
Scientific information can be good or harmful, moral or immoral. People must decide if the information is used to help or harm people. Science cannot make that decision.

PTS: 1 DIF: Webb's III OBJ: 5/3 STA: SC.H.3.3.4

114. ANS:
Antibiotic 2 is more effective (fewer bacteria were still alive at the end of the experiment in Figure 1-1). Culture E serves as a control.

PTS: 1 DIF: Webb's II OBJ: 3/2 STA: SC.H.1.3.3 SC.H.1.3.4

115. ANS:
c, d, a, b, f, e

PTS: 1

116. ANS:
New discoveries lead to new products that people can use every day. Examples of new products include movies, videotapes, DVDs, medicines, and satellite tracking systems.

PTS: 1

117. ANS:
Data may be recorded or summarized in the form of tables, charts, graphs, or written text.

PTS: 1

118. ANS:
You could place equal amounts of water and one thermometer in each beaker. Then place one beaker on each hot plate. Add salt to only one beaker. Heat both beakers until the water boils, then check the temperature for the boiling point of each. Compare the boiling point of the water alone to that of the water with salt added. Repeat with several trials to verify results.

PTS: 1

119. ANS:
1. problem
2. hypothesis
3. variables
4. controls
5. analyze
6. conclusions

PTS: 1

120. ANS:
Science is a way or process to investigate what is happening around us. Technology is the application of science to make products or tools that people can use.

PTS: 1

121. ANS:
Answers will vary depending on object, but should include defining its need, a scientific discovery on which the object is based, and how it was made into a product.

PTS: 1

122. ANS:
As an artifact, each of the individual components (computer, modem, transmission lines) are all hardware technology. As a technique, it is a new means of communication. As a social-technical system, it has changed how people interact with each other.

PTS: 1

123. ANS:
Define the problem, search for solutions, engineering production, test the model, produce the product.

PTS: 1

124. ANS:
It allows scientists from all over the world to understand each other’s work. And, since the units are based on units of ten, multiplication and division are easy to do.

PTS: 1

ESSAY

125. ANS:
No, because it would be impossible to tell which variable had caused the effect observed. Only one variable at a time can be changed.

PTS: 1

126. ANS:
Answers will vary: An experiment might call the hypothesis into question, or new information might be learned.

PTS: 1

127. ANS:
Answers will vary. May include: medicines, maps, thermometers, telescopes; microscopes. Accept all reasonable answers.

PTS: 1

128. ANS:
Answers will vary depending on the problem described, but should include: a definition of the problem, a proposed solution, how the concept was tested, and final product.

PTS: 1

Monday, December 17, 2007

6th Grade - Chapther 20 Test REVIEW

6th Grade TEST - Chapter20 ONLINE REVIEW

True/False
Indicate whether the statement is true or false.

____ 1. Water waves can move a piece of cork floating on top of the water only in an up and down motion.

____ 2. Mechanical waves can travel in any type of medium.

____ 3. Radio waves are the only type of electromagnetic wave that is a transverse wave.

____ 4. Sound waves are compressional waves.

____ 5. The amplitude of a wave is the distance between a point on one wave and the identical point on the next wave.

____ 6. In general, the more energy a wave has the greater its amplitude.

____ 7. The speed of light depends on the medium it travels through.

____ 8. You can see yourself in a mirror because of the wave property called interference.

____ 9. Refraction occurs when the amplitude of a wave changes as it goes from one medium to another.

____ 10. You can hear sounds around the corner of a door due to the wave property called diffraction.

____ 11. High-pitched sounds have high frequencies, and low-pitched sounds wave low frequencies.

____ 12. Amplitude and frequency may vary in waves, but all waves travel at the same speed.

____ 13. Waves travel in straight lines and therefore cannot bend as they pass through a narrow opening.

____ 14. Mechanical waves transmit matter, while electromagnetic waves transmit energy.

____ 15. When you watch lightning, the light reaches you before the sound of the accompanying thunder because light travels faster than sound.

____ 16. Diffraction causes diamonds and other gems to sparkle.

____ 17. In a mechanical compressional wave, the wave energy causes the matter in the medium to move up and down or back and forth at right angles to the direction the wave travels.

____ 18. A group of molecules that are squeezed together is called a compression.

Multiple Choice
Identify the choice that best completes the statement or answers the question.

____ 19. What is the best description of a wave?
a.
A wave transfers matter from one place to another.
b.
A wave transfers energy from one place to another.
c.
A wave transfers both energy and matter.
d.
A wave moves matter from one place to another.


____ 20. What kind of wave is created when an up and down motion of a rope produces right angles?
a.
compressional wave
b.
sound wave
c.
tranverse wave
d.
electromagnetic wave


____ 21. What kinds of waves do satellites use to transmit their locations to global positioning systems?
a.
electromagnetic radio waves
b.
infrared waves
c.
ultraviolet waves
d.
visible light waves


____ 22. What is the scientific term used to describe the amount of energy transferred by a wave?
a.
amplitude
b.
compression
c.
frequency
d.
vibration


____ 23. The school band is practicing their scales. As the pitch and frequency of the notes increases, what happens to the wavelength of the notes?
a.
The wavelength increases.
b.
The wavelength decreases then increases.
c.
The wavelength stays the same.
d.
The wavelength decreases.


____ 24. From the information on the chart, what can you conclude about the way sound travels?
a.
Sound waves travel faster as the temperature decreases.
b.
Sound waves travel more slowly through air.
c.
Sound waves travel faster as the temperature increases.
d.
Sound waves travel at a constant speed in all temperatures.


____ 25.
What kind of sound is an echo?
a.
diffraction
b.
reflection
c.
refraction
d.
vibration


____ 26. When the band is practicing in the music room, you can hear the music as it passes through the hallway. What property of sound does this example describe?
a.
amplification
b.
diffraction
c.
refraction
d.
vibration


____ 27. What happens when two waves meet?
a.
They collide and change direction.
b.
They collide and continue moving.
c.
They pass through each other and continue moving.
d.
They crash together and form a tsunami.


____ 28. When two waves overlap, they combine to form a new wave. What is this characteristic called?
a.
crest
b.
diffraction
c.
interference
d.
trough


____ 29. You are giving a presentation in science class about sound. You describe how the noise produced by the motor of a lawn mower hurts your ears.What term would you use to explain the way that you would reduce the noise of the mower?
a.
constructive interference
b.
destructive interference
c.
reflected sound
d.
refracted sound


____ 30. What kind of a wave travels along the coils of a spring?
a.
amplitude
b.
compressional
c.
frequency
d.
transverse


____ 31. The electromagnetic spectrum shows the range of electromagnetic waves. The wavelengths decrease at the bottom of the spectrum and increase at the top. What is the explanation for the range of wavelengths?
a.
Each wavelength is a different distance from the sun.
b.
Each wavelength has a different amplitude of vibration.
c.
Each wavelength has a different level of refraction.
d.
Each wavelength has a different frequency.


____ 32. Which one of the following is NOT an example of a mechanical wave?
a.
sound wave
c.
earthquake wave
b.
water wave
d.
radio wave


____ 33. Which one of the following is NOT an example of an electromagnetic wave?
a.
sound wave
c.
red light
b.
x-rays
d.
gamma rays


____ 34. Which one of the following is NOT an example of a compressional wave?
a.
wave moving through a coiled spring
b.
sound traveling through the air
c.
sound traveling through water
d.
green light traveling through the air


____ 35. Tsunamis have a large amount of energy because of their large ____.
a.
wavelength
c.
frequency
b.
amplitude
d.
diffraction


____ 36. Which one of the following determines the color of a light wave?
a.
amplitude only
c.
wavelength and frequency
b.
wavelength and amplitude
d.
interference patterns


____ 37. A place where molecules are far apart is a ____.
a.
refraction
c.
rarefaction
b.
reflection
d.
compression


____ 38. The speed of sound through air is about ____.
a.
340 m/s
c.
3,000,000 m/s
b.
2,000,000 m/s
d.
3,000,000 m/hour


____ 39. When light bounces off a surface it is called ____.
a.
reflection
c.
diffraction
b.
refraction
d.
interference


____ 40. In which one of the following cases will refraction occur?
a.
light traveling from air to glass
b.
light reflecting off of a mirror
c.
light bending around the corner of a door
d.
green light interfering with blue light


____ 41. Constructive interference occurs when waves meet ____.
a.
crest-to-crest and trough-to-trough
b.
crest-to-trough and crest-to-trough
c.
trough-to-crest and trough-to-crest
d.
crest-to-crest


____ 42. Waves can ____ when they move from one medium to another.
a.
disappear
c.
bend
b.
interfere
d.
split


____ 43. A(n) ____ wave DOES NOT need matter for energy transfer.
a.
electromagnetic
c.
compressional
b.
mechanical
d.
sound


____ 44. In a mechanical ____ wave, matter moves at a right angle to the wave direction.
a.
compressional
c.
light
b.
transverse
d.
electromagnetic


____ 45. The speed of sound in water is ____ the speed of sound in air.
a.
greater than
c.
equal to
b.
less than
d.
not greater than


____ 46. A region of spread-out particles in a compressional wave is called a(n) ____.
a.
compression
c.
interference
b.
rarefaction
d.
medium


____ 47. Waves can combine with each other; this is called ____.
a.
interference
c.
compression
b.
wave addition
d.
rarefaction


____ 48. Wave frequency is the ____ of waves passing a given point per second.
a.
amplitude
c.
speed
b.
wavelength
d.
number


____ 49. In a(n) ____ wave, matter moves back and forth in the same direction as the wave.
a.
compressional
c.
light
b.
transverse
d.
electromagnetic


____ 50. The action of a wave bouncing off a surface is called ____.
a.
rarefaction
c.
reflection
b.
refraction
d.
diffraction


____ 51. Amplitude reflects the amount of ____ in a wave.
a.
energy
c.
rarefaction
b.
compression
d.
speed


____ 52. A(n) ____ is the distance between a point on one wave and the identical point on the next wave.
a.
amplitude
c.
frequency
b.
wavelength
d.
compression


____ 53. The ____ of waves can change when the waves move from one medium to another.
a.
altitude
c.
speed
b.
amplitude
d.
compression


____ 54. A mechanical wave can travel only through ____.
a.
air
c.
matter
b.
water
d.
a vacuum


____ 55. The action of a wave bending around a barrier is called ____.
a.
reflection
c.
refraction
b.
diffraction
d.
rarefaction


____ 56. For significant ____ to occur, the wavelengths should match the size of the opening they are passing through.
a.
reflection
c.
refraction
b.
diffraction
d.
rarefaction


Completion
Complete each statement.

57. Waves are rhythmic disturbances that carry energy through matter or space without transferring ____________________.

58. Since sound is a mechanical wave it needs a ____________________ to travel through.

59. Waves that do not require matter to transfer energy are ____________________ waves.

60. ____________________ waves can be either transverse or compressional.

61. The less dense area of a compressional wave is called a(n) ____________________.

62. In a compressional wave, the amount of compression is like the ____________________ of a transverse wave.

63. The ____________________ is the unit of measure for the frequency of wavelengths per second.

64. Sound travels faster in ____________________ than in liquids.

65. An electromagnetic wave is slowed down if many ____________________ are in the medium.

66. Hertz can be described as ____________________.

67. The echo of a sound wave is due to ____________________ of the sound wave.

68. When light slows down as it passes from air to water it bends toward the ____________________.

69. The change in direction of waves when the wave travels from air to glass is ____________________.

70. Diffraction occurs when waves ____________________ around the edge of a barrier.

71. When two waves interact and their amplitudes cancel out, ____________________ interference has occurred.

72. Waves are ____________________ if they bounce off a surface.

73. Mechanical waves can be transverse or ____________________ waves.

74. The property of waves that allows them to bend around a barrier is ____________________.

75. Waves may bend if they move from one ____________________ to another.

76. Waves do not carry matter, but they do carry ____________________.

77. Wavelength, frequency, amplitude, and ____________________ are four characteristics of waves that can change.

78. In visible light, color is an indication of ____________________.

79. The common name for the reflection of sound waves is an ____________________.

80. In a compressional wave, one wavelength is the distance between adjacent compressions or adjacent ____________________.

81. Light waves travel more ____________________ as they enter water.

82. When light is reflected from a rough surface, the reflected light ____________________, producing no image.

83. Waves ____________________ best when their wavelength is similar in size to the opening they are moving through.

Matching

Match each item with the correct statement below.
a.
compressional wave
d.
mechanical wave
b.
electromagnetic wave
e.
transverse wave
c.
interference



____ 84. does not require a medium to travel through

____ 85. light waves and water waves are examples of this

____ 86. interaction of various different waves

____ 87. can be either transverse or compressional

____ 88. sound waves are an example of this

Match each item with the correct statement below.
a.
amplitude
d.
reflection
b.
diffraction
e.
refraction
c.
frequency



____ 89. the pitch of a sound wave

____ 90. why light shines off of a mirror

____ 91. related to the energy of a wave

____ 92. the changing of the speed of a wave

____ 93. the spreading out of waves around a barrier

Match each term with the correct description below.
a.
amplitude
j.
medium
b.
compression
k.
wave speed
c.
compressional wave
l.
rarefaction
d.
diffraction
m.
reflection
e.
electromagnetic wave
n.
refraction
f.
frequency
o.
transverse wave
g.
constructive interference
p.
wave
h.
destructive interference
q.
wavelength
i.
mechanical wave



____ 94. Squeezing a group of particles in a wave

____ 95. A transverse or compressional wave that can travel only through matter

____ 96. The matter through which a wave transfers energy

____ 97. A wave bends around a barrier

____ 98. A mechanical wave in which matter moves at right angles to the wave direction

____ 99. A wave in which matter moves back and forth in the direction the wave is moving

____ 100. A wave that doesn’t require matter to transfer energy

____ 101. A region of spread-out particles in a wave

____ 102. The distance from the crest or trough of a wave to the rest position

____ 103. The action of a wave bouncing off an object

____ 104. The number of waves passing a given point per second

____ 105. The product of wavelength and frequency

____ 106. A combination of waves form a smaller wave

____ 107. A combination of waves form a larger wave

____ 108. A rhythmic disturbance that carries energy

____ 109. A wave bends as it moves from one medium to another

____ 110. The distance between a point on a wave and the identical point on the next wave

Short Answer

111.
Explain how electromagnetic waves emitted by the sun affect you everyday.

112.
A boat in a lake is subjected to passing water waves. Describe the motion of the boat.

113.
Describe why you could not hear someone talk if you were both on the surface of the Moon.

114.
How can light travel from the Sun to Earth through the vacuum of space?

115.
How do your vocal cords produce sounds?

116.
Explain why a bright light differs from a dim light in terms of the amplitudes of each light wave.

117.
An instrument plays a pitch of 266 Hz. Another identical instrument plays a pitch of 400 Hz. How do the wavelength of each of these sound waves compare?

118.
Light that reflects off some surfaces can cause glare. Why don't all surfaces cause glare?

119.
A pencil is placed in a bucket of water. In some views, the pencil in the water will look bent when compared to the pencil above the water. Why is this so?

120.
Why is diffraction of light hard to detect?

121.
Describe how ear protectors help protect against hearing damage.

122. Study the following diagram. Then label the wave using the terms from the list.

amplitude
crest
trough
wavelength


123. Explain how the destructive interference of sound waves can help preserve hearing.

124. If the statement or term identifies a mechanical wave, list its letter under Mechanical Wave. If it identifies an electromagnetic wave, list its letter under Electromagnetic Wave. One or more terms might belong in both categories.

a. radio wave
d. visible light
g. transverse wave
b. sound wave
e. ocean wave
h. tidal wave
c. x rays
f. compressional wave
i. microwave

Mechanical Wave
Electromagnetic Wave
_____
_____
_____
_____
_____
_____
_____
_____
_____
_____
_____
_____


125. Compare and contrast transverse waves and compressional waves, and give an example of each type.

126. Calculate the wave speed of a 500-Hz wave with a wavelength of 0.5 m. First write the equation, then solve the problem, showing your work.

127. Assume that you hear a very low but very loud sound. What can you infer about the frequency and the amplitude of the sound waves you hear?

Problem

Figure 16-1

128. In Figure 16-1, what is the wavelength of Wave A?

129. In Figure 16-1, what is the wavelength of Wave B?

130. In Figure 16-1, what is the amplitude of Wave A.

131. In Figure 16-1, what is the amplitude of Wave B?

132. In Figure 16-1, which wave has the greater frequency?

133. In Figure 16-1, which wave has the least amount of energy?

134. When sunlight passes through a piece of glass known as a prism, the sunlight gets separated into the colors of the rainbow. Use the concept of refraction to explain how this occurs.

Essay

135.
Explain the differences and similarities between waves and particles.

Identify and explain what is responsible for each of the following effects.

136. You see a car behind you in the rearview mirror of your car.

137. You see a coin at the bottom of a fountain of water, but when you reach for it, it is in a different place than it appears to be.

138. You are in a cave with light coming in through a narrow crack in the ceiling. You can see a distinct beam of light on the floor, and you can see features of the cave illuminated by dim light.

139. Members of an orchestra tune their instruments before they begin to play. This produces a blast of confusing, disharmonious noise. When they begin to play in unison, the music from each instrument group is clear and loud. Explain these effects in terms of two types of interference.

7th Grade - Chapter 5 Test Review

7th Grade REVIEW TEST - Chpater 5

True/False
Indicate whether the statement is true or false.

____ 1. When you perform work on an object you increase the energy of the object.

____ 2. A force at any angle to the direction of motion can perform work.

____ 3. Work is measured in joules.

____ 4. All forms of energy can do work.

____ 5. Under certain conditions, it is possible to get more work out of a machine than you put into it.

____ 6. Power is the rate at which a force is applied.

____ 7. The unit of power is the watt.

____ 8. Machines may allow you to do less work over a longer distance.

____ 9. The thread around a screw is a lever.

____ 10. The mechanical advantage of a wheel and axle is the radius of the wheel divided by the radius of the axle.

____ 11. A broom is an example of a wedge.

____ 12. Power and work are interchangeable terms.

____ 13. If you use a ramp that is 6 m long to move an object upward 1 m, then the mechanical advantage of the ramp is 6.

____ 14. You are doing NO work when you hold your 23-kg dog in your arms.

____ 15. You do 1 J of work if you use a force of 1 N for a distance of 1 m.

Multiple Choice
Identify the choice that best completes the statement or answers the question.

____ 16. Which is NOT an example of a compound machine?
a.
bicycle
b.
can opener
c.
pulley
d.
scissor


____ 17. Jacob is pushing a shopping cart down a supermarket aisle. He is exerting forces in different directions on the shopping cart handle. Which force is doing the work?
a.
downward force
b.
forward force
c.
right angle force
d.
upward force


____ 18. Which response best describes power?
a.
The distance an object is moved.
b.
The force exerted on an object.
c.
The motion of an object.
d.
The rate at which work is done.


____ 19. In which way can a machine NOT make work easier?
a.
changing the amount of force needed
b.
changing the distance over which force is exerted
c.
changing the direction in which force is exerted
d.
changing the work by creating a new force


____ 20. Joey used a knife to cut a piece of bread. What is the work he applied to the knife called?
a.
friction
b.
input force
c.
mechanical advantage
d.
output force


____ 21. Hu made a chart to show the efficiency of three different machines.


Which machine has the highest ratio of output work to input work?
a.
Machine 1
b.
Machine 2
c.
Machine 3
d.
cannot tell


____ 22. Which is an example of a wheel and axle?
a.
baseball bat
b.
doorknob
c.
pulley
d.
screw


____ 23. How are an inclined plane and a wedge alike?
a.
Both have a flat, sloped surface.
b.
Both are compound machines.
c.
Both have the same mechanical advantage.
d.
Both have the same output force.


____ 24. Darren draws a diagram to show the forces exerted on an object. The arrows represent equal forces on the object.


How will the object be affected by the two equal forces?
a.
It will break.
b.
It will change direction.
c.
It will not be affected.
d.
It will not move.


____ 25. Which word best describes the ratio of an output force to an input force?
a.
distance
b.
efficiency
c.
friction
d.
mechanical advantage


____ 26. How does friction affect a machine’s efficiency?
a.
It increases it.
b.
It decreases it.
c.
It keeps it consistent.
d.
It does not affect it.


____ 27. The work equation states that work in joules equals force in newtons times distance in meters. If Sarah carries a box that weighs 35 N a distance of 3 m, how much work did she do?
a.
38 J
b.
70 J
c.
105 J
d.
175 J


____ 28. Tammy is standing still while holding a ten-pound bowling ball. Is she doing work?
a.
Yes, the ball is heavy.
b.
Yes, she is exerting a force on the object.
c.
No, she is not making the object move.
d.
No, she is exerting a force on the ground.


____ 29. Which one of the following is NOT an example of work being done?
a.
the Moon orbiting Earth
b.
pushing a box from the bottom of a hill to the top of the hill
c.
pulling a sled across a field covered with snow
d.
lifting a bookbag off the floor


____ 30. A fixed, single pulley that is used to lift a block does which one of the following?
a.
doubles the force required to lift the block
b.
decreases the force required to lift the block
c.
makes the block easier to lift by changing the direction of the force needed to lift it
d.
decreases the force required and changes the direction of the force required


____ 31. A slanted surface used to raise an object is a(n)____.
a.
efficiency board
c.
inclined plane
b.
effort ramp
d.
wedge


____ 32. A device that does work with only one movement and changes the size or direction of a force is a(n) ____.
a.
compound machine
c.
screw
b.
effort machine
d.
simple machine


____ 33. A bar that is free to pivot about a fixed point is a ____.
a.
fulcrum
c.
ramp
b.
lever
d.
wedge


____ 34. The rate at which work is done is called ____.
a.
efficiency
c.
force
b.
effort time
d.
power


____ 35. The work output of a machine divided by the work input is the ____ of the machine.
a.
efficiency
c.
power
b.
effort
d.
resistance


____ 36. The amount by which a machine multiplies an input force is called the ____.
a.
efficiency factor
c.
mechanical advantage
b.
fulcrum
d.
resistance force


____ 37. An inclined plane with one or two sloping sides forms a machine called a ____.
a.
pulley
c.
ramp
b.
lever
d.
wedge


____ 38. An inclined plane wrapped around a cylinder post is a ____.
a.
lever
c.
screw
b.
ramp
d.
wedge


____ 39. A machine that changes only the direction of a force has a mechanical advantage of ____.
a.
1
c.
10
b.
2
d.
100


____ 40. A winding mountain road is an example of a(n) ____.
a.
lever
c.
wedge
b.
inclined plane
d.
wheel and axle


____ 41. When two or more simple machines work together, they are called a(n) ____.
a.
compound machine
c.
screw
b.
effort machine
d.
simple machine


____ 42. A lever with a mechanical advantage greater than 1 is used to ____.
a.
change direction
c.
increase force
b.
increase distance
d.
decrease force


____ 43. Three of the following simple machines are basically the same. The one that does NOT belong with the group is the ____.
a.
lever
c.
wedge
b.
pulley
d.
wheel and axle


____ 44. An object is moving due east. You push the object. Work is being done at all times when you push ____.
a.
due west
c.
straight down
b.
due east
d.
at a 45° angle


____ 45. A ____ is an example of a compound machine.
a.
lawnmower
c.
baseball bat
b.
shovel
d.
wheel and axle


____ 46. The mechanical advantage tells you the number of times a machine increases the ____.
a.
net force
c.
output force
b.
stable force
d.
input force


____ 47. Work is equal to force times ____.
a.
power
c.
joules
b.
distance
d.
energy


____ 48. Power is measured in J per ____.
a.
watt
c.
minute
b.
hour
d.
second


____ 49. In order for work to be done, an object must ____.
a.
have mass
c.
have muscles
b.
move in the direction of the force
d.
move at a right angle to the force


____ 50. Machines let you use less force over a greater ____.
a.
distance
c.
weight
b.
mass
d.
exertion


____ 51. NO work is being done when you ____ a ball.
a.
hit
c.
carry
b.
catch
d.
drop


____ 52. When the Egyptians built the pyramids, they used the idea that a large force over a short distance can be accomplished by the same work as a small force over a ____ distance.
a.
changing
c.
shorter
b.
minimum
d.
long


____ 53. ____ describes the rate at which work is being done.
a.
Joules
c.
Effort force
b.
Power
d.
Efficiency


____ 54. A ____ is NOT a simple machine.
a.
wrench
c.
tooth
b.
shovel
d.
teeter-totter


____ 55. The pivot point of a lever is called a ____.
a.
wedge
c.
fulcrum
b.
screw
d.
wheel and axle


____ 56. Power is expressed in units of ____.
a.
light
c.
joules
b.
watts
d.
surges


____ 57. A(n) ____ is a moving inclined plane.
a.
teeter-totter
c.
elevator
b.
staircase
d.
wedge


Completion
Complete each statement.

58. When force is _________________________ to the direction of motion, no work is done.

59. A joule is equal to one ____________________ times one meter.

60. When you use a crowbar to lift a large rock, you are working against the force called ____________________.

61. Power describes the ____________________ at which work is being done.

62. Unlike a fixed pulley, a movable pulley ____________________ the input force.

63. Doorknobs and faucet handles are examples of a simple machine called a(n) ______________________________.

64. An ideal machine has an efficiency of ____________________.

65. The pivot point of a lever is called the ____________________.

66. A machine made of several simple machines is called a(n) ______________________________.

67. When a machine is used to perform a task, work output is always ____________________ than work input.

Choose the term in parentheses that correctly completes the sentence.

68. A blender is a ____________________ (simple, compound, pulley) machine.

69. The mechanical advantage that makes work easiest is one that is ____________________ (large, small, zero).

70. Holding a watermelon in your hands is an example of ____________________ (work, no work) being done.

71. A goalie stopping a hockey puck is an example of ____________________ (work, no work) being done.

72. Power does NOT depend on ____________________ (work done, muscles, time).

73. As you increase the effort distance, you ____________________ (decrease, increase, stabilize) the effort force needed.

74. The mechanical advantage tells you the number of times a machine ____________________ (increases, decreases, eliminates) the effort force.

75. A ____________________ (shovel, crowbar, potter’s wheel) is NOT an example of a lever.

76. An ideal machine has an efficiency ____________________ (less than one, equal to one, greater than one).

77. ____________________ (Heat, Friction, Work) is NOT a source of energy loss in a machine.

Matching

Match each term with the following questions.
a.
input force
d.
output force
b.
efficiency
e.
compound machine
c.
mechanical advantage



____ 78. ratio of output force to input force

____ 79. force you apply to a simple machine

____ 80. force you overcome when using a simple machine

____ 81. device made of more than one simple machine

____ 82. ability of a machine to convert work input into work output

Match each simple machine with the machines below.
a.
inclined plane
d.
lever
b.
wedge
e.
wheel and axle
c.
screw



____ 83. knife

____ 84. leaf rake

____ 85. wheelchair ramp

____ 86. potter's wheel

____ 87. threaded bolt

Match each item with the correct description below.
a.
simple machine
j.
watt
b.
work
k.
ideal machine
c.
input force
l.
screw
d.
inclined plane
m.
pulley
e.
joule
n.
mechanical advantage
f.
output force
o.
efficiency
g.
power
p.
fulcrum
h.
machine
q.
wheel and axle
i.
friction
r.
wedge


____ 88. a device that makes work easier by changing the size or direction of the applied force

____ 89. SI unit for work

____ 90. causes the output work of a machine to be less than the input work

____ 91. the rate at which work is being done

____ 92. the ratio of the output force to the input force

____ 93. a moving inclined plane

____ 94. has only one movement

____ 95. the unit of measurement of power

____ 96. two rigidly attached wheels that rotate together

____ 97. a sloped surface

____ 98. exertion of a force on an object that produces motion in the direction of the force

____ 99. the force a machine exerts

____ 100. a machine’s ability to convert work input into work output

____ 101. machine with 100% efficiency

____ 102. the pivot point of a lever

____ 103. an inclined plane wrapped around a shaft

____ 104. a grooved wheel that redirects force using a rope

____ 105. the effort force you exert

Short Answer

106.
Explain how a wheel and axle works and give examples of objects that use a wheel and axle.

107.
Sharon wants to know if friction will affect the efficiency of a ramp that she built. She will form a hypothesis and then test it.

Part A Write a hypothesis that Sharon can test.

Part B Write a plan that shows how Sharon can test her hypothesis.

108.
What does work depend on in scientific terms?

109.
You swing a rope in a circle. Are you doing work on the rope? Why or why not?

110.
Which one of the following could be the mechanical advantage of a third-class lever: 0.7, 1.5, 10.5, or 3.0? Explain your answer.

111.
An inventor claims to have built a machine that can produce 120 J of work with an input of 110 J. Would you believe the inventor's claim? Why or why not?

112.
Explain why tin snips, designed for cutting metal, have long handles and short blades.

113.
How are work, time, and power related?

114.
Gears are modified wheel-and-axle machines. Explain how to calculate the mechanical advantage of a pair of gears.

115.
A 700-watt gasoline engine and a 300-watt electric motor both do 3 J of work. Which machine can do the work faster? Explain your answer.

116.
How does low air pressure in bicycle tires reduce the efficiency of a bicycle?

117.
Give one example of a compound machine and list the simple machines that make it up.

118.
Do machines make work easier? Explain your answer.

119.
How does oil reduce friction between two surfaces?

120.
Explain how your teeth work as a wedge.

121.
Explain the transfer of energy during work.

Complete the table below by calculating the missing values. Then answer the following questions.

Situation
Force
Distance
Time
Work
Power
1. A
200 N
50 m
10 s


2. B
100 N
6 m


200 W
3. C
200 N
100 m
10 s


4. D
200 N

10 s
5000 J



122. What are the missing values in line 1?

123. What are the missing values in line 2?

124. What are the missing values in line 3?

125. What are the missing values in line 4?

126. In which situation was the most work done?

127. In which situation was the most power used?

128. How does the work done in situation D compare to that done in situation A?

129. How does the distance in situation D compare to the distance in situation A?

130. What would happen to the power in situation C if the time doubled?

131. Compare and contrast simple and compound machines.

132. Compare and contrast a screw and a wedge.

133. What is the work done in using a force of 200 N to push a box 15 m?

134. What is the power used if it took 2,000 J to move a box in 8 s?

135. What is the mechanical advantage of using a machine if you use an input force of 25 N to overcome an output force of 125 N?

136. If an output force of 50 N is used to move an object a distance of 20 m, what distance must the object be moved if the input force is 10 N, so that work in = work out?

137. What is the efficiency of a machine if the work input is 75 N and the work output is 25 N?

Problem

138.
You use 200 N of force to push a snow shovel 10 m along the ground. How much work was done?

139.
A painter lifts a 3 kg can of paint 3 m above the floor. How much work was done?

140.
How much power is needed to do 1,000 J of work on a box if it takes 50 s to lift it?

141.
How much work is done if 500 W of power is used over 2 min?

142.
Calculate the mechanical advantage of a lever where 5 N of input force is needed to move a 10 N box using that lever.

143.
A carpenter uses a claw hammer to pull a nail from a board. The nail has a resistance of 1,500 N. The carpenter applies a force of 150 N. What is the mechanical advantage of the hammer?

Essay

144. Name the six types of simple machines and give an example of each, or what each might be used to do.

145. Explain why applying force to an object does not always result in work being done.

146. Even though work input should equal work output, explain why, other than on ideal machines, machines have an efficiency less than one.

147. If a machine cannot have more work output than work input, what advantage is there to using one?

148. Compare and contrast fixed pulleys with movable pulleys and pulley systems and discuss their respective mechanical advantages.

Wednesday, December 5, 2007

6th Grade Chapter 18 REVIEW

Below you will find all the possible questions on the test as well as many more. If you want to check your answers with me you may come to Tutoring on Thursday or see me Friday Morning.

6th Grade - Chapter 18 TEST

True/False
Indicate whether the statement is true or false.

____ 1. During energy transformations, sometimes energy is destroyed.

____ 2. The greater the average kinetic energy of an object, the lower the temperature of that object.

____ 3. When you pick up an ice cube, the heat from your hand transfers to the ice.

____ 4. When you are swinging on a playground swing, your potential energy is greatest at the highest point.

____ 5. A vinyl-covered seat conducts heat slower than a fabric-covered seat.

____ 6. The stored potential energy within chemical bonds is called chemical energy.

____ 7. Photosynthesis is primarily an exothermic reaction.

____ 8. Catalysts are used in the production of many consumer goods such as vegetable shortening and synthetic rubber.

Multiple Choice
Identify the choice that best completes the statement or answers the question.

____ 9. Energy cannot be created or destroyed, but only changed from one form to another. What is this statement known as?
a.
the law of conservation of energy
b.
the law of thermal energy
c.
the rule of energy
d.
the rule of nuclear energy


____ 10. A microwave oven and an X-ray machine use what kind of energy?
a.
kinetic
b.
nuclear
c.
potential
d.
radiant


____ 11. Mary places a ball at the top of an inclined plane.
What type of energy does the ball have?
a.
chemical energy
b.
kinetic energy
c.
potential energy
d.
thermal energy


____ 12. Joe is boiling a pot of water.
What process forces the warmer water to the top?
a.
convection
b.
kinetic energy
c.
law of conservation of energy
d.
potential energy


____ 13. Erica is tossing a ball up and down in her hand. The mechanical energy of the ball is slightly less when she catches it than when she tossed it upward. What does this demonstrate?
a.
some chemical energy is converted into mechanical energy
b.
some mechanical energy is converted into thermal energy
c.
some thermal energy is converted into mechanical energy
d.
some mechanical energy is converted into radiant energy


____ 14. Manuel’s father makes a snack in a microwave oven and dinner on the stove. Which kinds of energy transfers does he use to cook the food?
a.
conduction and thermal
b.
convection and conduction
c.
radiation and conduction
d.
radiation and convection


____ 15. Which is the name for the energy of the particles of an object due to their random motion?
a.
conduction
b.
convection
c.
radiation
d.
thermal


____ 16. Why is copper sometimes used on the bottom of cooking pans?
a.
Copper is easy to attach to the bottom of cooking pans.
b.
Copper conducts heat more evenly than many other metals.
c.
Copper conducts radiation evenly across the pan bottom.
d.
Copper is less expensive and more attractive than plastic.


____ 17. The amount of useful energy decreases as energy changes forms. Why is this so?
a.
Thermal energy is changed to kinetic energy, which leaves less useful energy.
b.
Kinetic energy is changed to potential energy, which leaves less useful energy.
c.
Thermal energy is produced, only some of which is useful.
d.
Radiant energy is produced, which becomes less concentrated.


____ 18. Energy occurs in ____.
a.
only one form
c.
only three forms
b.
only two forms
d.
many forms


____ 19. What are the two main types of energy that relate to motion?
a.
conduction and convection
c.
potential and kinetic
b.
solar and thermal
d.
radiation and heat


____ 20. A rock sitting on top of a cliff has ____.
a.
kinetic energy
c.
potential energy
b.
no energy
d.
radiation energy


____ 21. As the temperature of a material increases, the average ____ of its particles also increases.
a.
specific heat
c.
mass
b.
kinetic energy
d.
potential energy


____ 22. What is the freezing point of water on the Celsius temperature scale?
a.
0°C
c.
100°C
b.
–100°C
d.
273°C


____ 23. Which one of the following statements describes the flow of heat?
a.
Energy moves from a warmer object to a cooler object.
b.
Energy moves from a cooler object to a warmer object.
c.
Energy moves only between two warm objects.
d.
Energy moves only between two cold objects.


____ 24. A material that reduces the flow of heat by conduction, convection, and radiation is called a(n) ____.
a.
conductor
c.
insulator
b.
condenser
d.
radiator


____ 25. Which type of energy transfer occurs even in a vacuum?
a.
combustion
c.
convection
b.
radiation
d.
conduction


____ 26. Which one of the following is NOT a good conductor of heat?
a.
air
c.
copper
b.
aluminum
d.
silver


____ 27. An example of thermal energy transfer by convection is the ____.
a.
melting of ice
c.
heating of the ground by sunlight
b.
formation of air currents
d.
heating of the ocean by sunlight


____ 28. The total amount of energy in the universe ____.
a.
is always increasing
c.
remains the same
b.
varies from moment to moment
d.
is always decreasing


____ 29. The motion of atoms in all directions in solids, liquids, and gases is called ____.
a.
radiation
c.
random motion
b.
convection
d.
magnetism


____ 30. The Sun emits a form of energy called ____ energy.
a.
chemical
c.
radiant
b.
mechanical
d.
orbital


____ 31. Which are forms of energy?
a.
chemical, inertia, and radiant
b.
chemical, radiant, and thermal
c.
electrical, friction, and nuclear
d.
velocity, thermal, and chemical


____ 32. Temperature is a measure of the average kinetic energy of which of the following?
a.
the atmosphere
b.
liquid in a container
c.
the particles in an object
d.
the wind chill index


____ 33. Curtis is sipping a glass of juice. The ice in the glass has melted, and to him the juice and his hand seem to be about the same temperature. Why have the temperatures balanced?
a.
because of a transfer of energy caused by convection
b.
because of a transfer of thermal energy known as heat
c.
because of a transfer of kinetic energy known as heat
d.
because of a transfer of radiation caused by energy


____ 34. Where is the chemical energy in a material stored?
a.
the nucleus
c.
the protons
b.
the electrons
d.
the bonds between atoms


____ 35. Which one of the following is correct concerning the breaking of a chemical bond?
a.
Only electricity can break a chemical bond.
b.
Energy is never released from the breaking of a bond.
c.
Only heat can break a chemical bond.
d.
When a bond is broken, energy is added and released.


____ 36. Which type of chemical reaction needs to absorb energy to proceed?
a.
exothermic
c.
explosion
b.
endothermic
d.
radiation


____ 37. Which one of the following is NOT an example of a chemical reaction that is exothermic?
a.
the breakdown of water into hydrogen gas and oxygen gas
b.
a chemical hand warmer
c.
the burning of charcoal
d.
the explosion of dynamite


____ 38. Which one of the following statements is true about catalysts?
a.
They are required for a chemical reaction to take place.
b.
They change the rate of a chemical reaction without being used up.
c.
They change the rate of a chemical reaction but are always used up.
d.
They can only slow down the rate of a chemical reaction.


____ 39. The ability to cause change is ____.
a.
heat
c.
energy
b.
transformation
d.
conduction


____ 40. The average kinetic energy of the atoms in an object determines its ____.
a.
speed
c.
mass
b.
temperature
d.
specific heat


____ 41. Materials that do not transfer heat easily are ____.
a.
thermals
c.
insulators
b.
conductors
d.
metals


____ 42. At 0°C on the Celsius temperature scale, ____.
a.
water is room temperature
c.
water boils
b.
water freezes
d.
all particle motion stops


____ 43. Kinetic energy plays a role in each of the following EXCEPT a ____.
a.
moving soccer ball
c.
skier standing at the top of a hill
b.
skydiver falling toward Earth
d.
car traveling at 40 mph


____ 44. The scientist who described the law of conservation of energy is ____.
a.
Celsius
c.
Kelvin
b.
Fahrenheit
d.
Joule


____ 45. The transfer of energy from warmer to cooler objects is known as ____.
a.
heat
c.
temperature
b.
conservation
d.
absolute zero


____ 46. A bouncing rubber ball has each of the following EXCEPT ____.
a.
kinetic energy
c.
heat
b.
potential energy
d.
temperature


____ 47. Radiation involves the transfer of energy by ____.
a.
particle collisions
c.
air flow
b.
waves
d.
temperature differences


____ 48. The spring inside a moving wind-up toy has ____.
a.
potential energy only
b.
kinetic energy only
c.
both potential energy and kinetic energy
d.
neither potential energy nor kinetic energy


____ 49. If the amount of energy required to boil a pot of water were added to a swimming pool, the water in the pool would
a.
boil
c.
warm
b.
change very little
d.
cool


____ 50. As a snowflake falls, it ____.
a.
loses kinetic energy and gains potential energy
b.
loses potential energy and gains kinetic energy
c.
gains both potential and kinetic energy
d.
loses both potential and kinetic energy


____ 51. When you use a flashlight, you produce light and ____ energy.
a.
potential
c.
chemical
b.
nuclear
d.
thermal


____ 52. The transfer of thermal energy through liquids and gases is called ____.
a.
convection
c.
radiation
b.
conduction
d.
osmosis


Completion
Complete each statement.

53. If an object has energy, then that object has the ability to cause ____________________.

54. The higher a hill, the more ____________________ energy a skier has at the top and the more ____________________ energy while skiing down.

55. The statement that the total amount of energy in the universe never changes is called the ____________________.

56. The measure of the average ____________________ of particles in a material is called temperature.

57. Energy moves from the Sun to Earth by ____________________.

58. Cooking pans have handles made of materials that are ____________________ of heat.

59. When we move, our muscles transform chemical energy from our food into ____________________ energy and heat.

60. Heat is ____________________ by food as it cooks.

61. Any change of energy from one form to another is called a(n) ____________________.

62. The Fahrenheit temperature scale is used mainly in ____________________ and ____________________.

63. Energy moves through ocean currents by ____________________.

64. In photosynthesis, the cells in green plants convert energy from sunlight into ____________________energy in a type of sugar.

65. Catalysts in the body are called ____________________.

66. A(n) ____________________ in saliva acts as a catalyst to break down starches.

Unscramble the terms in italics next to their definitions. Write the terms on the lines provided.

67. fntorsaimotnar: change of energy from one form to another ____________________

68. teikinc: energy of objects in motion ____________________

69. slationur: material that doesn’t allow heat to be conducted easily ____________________

70. alw fo sornacetoniv fo gerney: Energy cannot be created or destroyed. ______________________________

71. dinutconoc: transfer of energy from particle to particle when there is a temperature difference ____________________

72. greyen: ability to cause change ____________________

73. athe: thermal energy that moves from a warmer to a cooler object ____________________

74. eptilonta: stored energy ____________________

75. tadaiorin: energy that travels in waves in all directions from its source ____________________

76. urepattmere: measure of the average kinetic energy of particles ____________________

77. ovitocencn: transfer of energy when particles move from place to place where there is a temperature difference ____________________

Complete the following sentences using the terms listed below.

thermals
conductors


78. ____________________ are materials that transfer thermal energy easily.

79. Columns of warm air that are forced up as cold air sinks are ____________________.

Matching

Match each term with the correct statement below.
a.
conduction
c.
heat
b.
convection
d.
radiation


____ 80. the movement of thermal energy from warm objects to cool objects

____ 81. Thermals in the air are due to this.

____ 82. type of energy movement used by microwave ovens

____ 83. reason why the handle of a spoon with only its bottom part in a pan of hot water can get hot

Match each term with the correct description below.
a.
endothermic
d.
potential energy
b.
exothermic
e.
temperature
c.
kinetic energy



____ 84. energy of motion

____ 85. celsius scale measures this

____ 86. energy of position

____ 87. a reaction that absorbs energy

____ 88. a reaction that releases energy

Short Answer

89.
An object has 12.57 J of energy. How many degrees Celsius could it warm one gram of water?

90.
Describe the ways that atoms move around in solids, liquids, and gases.

91.
A window is opened in a heated room during the winter. Explain why it feels cold inside the room after a while.

Figure 6-1

92.
In Figure 6-1, which car has the greatest potential energy?

93.
In Figure 6-1, which cars have the least potential energy?

94.
Can you determine which car in Figure 6-1 has the greatest kinetic energy? Explain your answer.

95. For each of the following examples, determine which type of heat transfer is illustrated.

a. Food is cooked in a microwave oven.
b. A breeze blows along the ocean shore on a hot day.
c. Food is cooked on a gas stove.
d. Food is cooked on a barbecue grill.

96. Study the diagram of the thermometer. Then complete the table below.



Boiling point
Freezing point
Current temperature
Fahrenheit
=Celsius
Celsius
100º

10º

Fahrenheit

32º




Consider a picture that shows a marshmallow added to a cup of hot cocoa then answer the following questions.

97. How does the thermal energy of the cocoa change when the marshmallow is added?

98. What happens to the temperature of the marshmallow?

99. What happens to the temperature of the cocoa?

100. By what means does the transfer of thermal energy take place?

101. To change a temperature from the Celsius scale to the Fahrenheit scale, you multiply the Celsius temperature by 9/5 and add 32 to the product. If the temperature is 30°C, what is the Fahrenheit temperature?

102.
Evan buys a flashlight for a camping trip. When he puts batteries in it, it shines brightly. What are the energy changes that take place to make the light shine?

103.
Name and describe the types of energy conversions that are involved when a person climbs stairs.

104.
What are two ways to change the rate of a chemical reaction?

105.
Contrast the way kinetic energy increases and the way potential energy increases.

106.
What is the difference between heat and temperature?

107.
Why are liquids such as alcohol used in thermometers?

108.
How do many people use radiation to cook food?

109.
Explain the ways energy moves when an ice cube is set on a sidewalk on a sunny day.

110.
How is chemical energy important in lifting a heavy object?

111.
Why do some cooking pans have copper bottoms?

112.
Is combustion an exothermic reaction or an endothermic reaction? Is photosynthesis an exothermic reaction or an endothermic reaction?

113.
How does your body use enzymes?

114. Identify a form of energy that is related to each change.

a. change in speed
b. change in position

115. How does the amount of energy in the batteries in a flashlight compare to the total amount of energy given off by the flashlight as light and heat?

116. To change a temperature from Celsius to Fahrenheit, you multiply the Celsius temperature by 9/5 and add 32 to the product. If the temperature is 40°C, what is the Fahrenheit temperature?

117. Two identical packages are placed on different shelves in a kitchen cabinet. One of the shelves is a foot higher than the other.

a. Which package has more potential energy? Why?
b. If both packages are pushed off the shelves with identical force, which package will have more kinetic energy?

Essay

118. Explain how temperature is different from heat.

119. Explain the law of conservation of energy.

Monday, November 26, 2007

7th Grade Chapter 4 Practice

The 62 questions on your test are from this bank. Study hard.
7th Grade - Chapter 4 Test - REVIEW

Modified True/False
Indicate whether the statement is true or false. If false, change the identified word or phrase to make the statement true.

____ 1. The speed you read on your speedometer is the constant speed. _________________________

____ 2. When you ride your bike around a corner at 10 m/s, you are accelerating. _________________________

____ 3. To determine if an object has changed position, you need to know it's position relative to another object. _________________________

____ 4. Acceleration is caused by any forces. _________________________

____ 5. An example of a contact force is magnetism. _________________________

____ 6. If an astronaut were to land on Jupiter, his mass would increase. _________________________

____ 7. Sliding friction keeps you in the seat when a car goes around a corner. _________________________

____ 8. Forces always occur alone. _________________________

____ 9. If you throw a ball into the air, Earth exerts a force on the ball. The ball in the air exerts no force. _________________________

____ 10. To locate a mall close to you, you need to know it's distance. _________________________

____ 11. You push on a book and it moves. The forces acting on it must be action-reaction forces. _________________________

____ 12. If an unbalanced force is acting on a rope, the rope will accelerate in the direction of the unbalanced force. _________________________

____ 13. An insect falls from a twenty-story building and walks away when he hits the sidewalk because of contact forces. _________________________

Multiple Choice
Identify the choice that best completes the statement or answers the question.

____ 14. Electric, magnetic, and gravitational forces are all examples of which type of force?
a.
balanced
b.
contact
c.
non-contact
d.
unbalanced


____ 15. Which of the following has a net force of zero?
a.
balanced force
b.
buoyant force
c.
gravitational force
d.
unbalanced force


____ 16. Max is pushing a book across a table. When he stops pushing, the book slows down and stops. This is an example of which force?
a.
air resistance
b.
buoyancy
c.
gravity
d.
sliding friction


____ 17. When does a gravitational force between two objects increase?
a.
when the mass of the objects increases
b.
when the speed of the objects increases
c.
when the mass of the objects decreases
d.
when the speed of the objects decreases


____ 18. Mark is traveling 3 mi north at 2 mph. Which of the following can be figured out with this information?
a.
acceleration
b.
average speed
c.
displacement
d.
velocity


____ 19. Susan made a diagram to show how the relationship between a buoyant force and gravity.


Which answer BEST describes the relationship shown in the diagram?
a.
Buoyancy and gravity together balance an object.
b.
Buoyant forces move at a faster rate than gravity.
c.
Gravity is more powerful than buoyancy.
d.
Objects do not know whether they will be pulled up or down


____ 20. The Average Speed equation states that average speed in meters per second equals distance in meters divided by time in seconds. If Jan travels 63 m in 7 s, what is her average speed?
a.
7 m/s
b.
9 m/s
c.
14 m/s
d.
63 m/s


____ 21. Donna measured the displacement and time for a traveling object.


What is the velocity of the object?
a.
2 km/h south
b.
3 km/h south
c.
4 km/h south
d.
6 km/h south


____ 22. Motion is change in ____.
a.
speed
c.
force
b.
velocity
d.
position


____ 23. ____ is rate of change of position.
a.
Speed
c.
Acceleration
b.
Velocity
d.
Displacement


____ 24. You travel 200 km in 2 h. Your ____ speed is 100 km/h.
a.
constant
c.
instantaneous
b.
average
d.
initial


____ 25. When a car slows down at a traffic light, it is ____.
a.
accelerating
c.
decreasing its displacement
b.
traveling at constant velocity
d.
changing direction


____ 26. The unit of force is ____.
a.
m/s
c.
the joule
b.
the hertz
d.
the newton


____ 27. When two birds are pulling on a worm and the worm moves toward the first bird, you know that the forces are ____.
a.
long-range
c.
unbalanced
b.
action-reaction
d.
balanced


____ 28. A planet is discovered that is the same size as Earth and has the same gravitational acceleration, but has twice the mass. If you weigh 700 N on Earth, on the new planet you would weigh ____.
a.
350 N
c.
1,400 N
b.
700 N
d.
2,800 N


____ 29. Every force has a(n) ____ force.
a.
reaction
c.
opposite
b.
long-range
d.
accelerating


____ 30. An object at rest remains at rest. An object in motion keeps moving in a straight line at a constant speed. Which of Newton’s laws of motion does this describe?
a.
first law
b.
second law
c.
third law
d.
first and third laws together


____ 31. Which law of motion says that the ground pushes back on you when you push down on it?
a.
first law
b.
second law
c.
third law
d.
fourth law


____ 32. When is an object NOT accelerating?
a.
when it changes speed
b.
when it changes direction
c.
when it changes force
d.
when it changes velocity


____ 33. According to Newton’s second law of motion, how is acceleration related to net force?
a.
When net force on an object increases, acceleration increases.
b.
When net force on an object decreases, acceleration increases.
c.
When acceleration changes, net force stays the same.
d.
When net force changes, acceleration stays the same.


____ 34. Which statement best describes Newton’s third law of motion?
a.
All forces are equal.
b.
An object at rest tends to stay at rest.
c.
Forces always act in pairs.
d.
Some forces have no reaction.


____ 35. You hear that a storm is moving 15 km/h north. You have been given the storm's ____.
a.
constant speed
c.
velocity
b.
acceleration
d.
average speed


____ 36. Inertia is a measure of the ____ of an object.
a.
weight
c.
constant speed
b.
mass
d.
acceleration


____ 37. An unbalanced force acting on an object causes it to ____.
a.
move at constant speed
c.
not change its velocity
b.
continue in a straight line
d.
accelerate


____ 38. The force that opposes motion is ____.
a.
a balanced force
c.
an accelerating force
b.
an unbalanced force
d.
friction


____ 39. You throw a ball into the air. As the ball leaves your hand, the force(s) acting on it is/are ____.
a.
gravity
c.
balanced
b.
your hand
d.
gravity and your hand


Completion
Complete each statement.

40. If you walk one mile to a store and one mile back, your distance is ____________________ and your displacement is ____________________.

41. Speeding up, slowing down, and going around curves are examples of ____________________.

42. A(n) ____________________ is a push or a pull.

43. A car going around a corner, hits an icy path, and skids off the road. This represents a change from rolling friction to ____________________ friction.

44. If you ride your bike 2 miles on a straight road between Gooseberry Junction and Happy Valley, your distance is ____________________ and your displacement is ____________________.

45. ____________________ is the change in velocity divided by the change in time.

46. If you are riding on a skateboard and it stops suddenly, your body keeps moving forward. This is because of ____________________.

47. Forces that change an object's motion by touching the object are ____________________ forces.

48. A spacecraft orbits the Earth at a constant speed. The forces acting on it must be ____________________.

49. Acceleration due to gravity at the Earth's surface is ____________________.

50. Wagons have wheels instead of runners because ____________________ friction is less than ____________________ friction.

51. When you catch a ball, the ball creates force on your hand. The reaction force is ____________________.

52. If you throw a ball into the air, at the top of the path the force(s) acting on the ball is/are ____________________.

Choose the term or phrase that best completes each sentence.

53. If you drive from New York to San Francisco by way of Mt. Rushmore, Yellowstone National Park, and Branson, Missouri, your distance traveled is ____________________ (greater than, less than, the same as) your displacement.

54. When your feet push on the floor so that you can walk across the room, you move but the floor doesn’t. The force of the floor on your feet is ____________________ (greater than, less than, the same as) the force of your feet on the floor.

55. Standing still in a windstorm is an example of ____________________ (static, sliding, rolling) friction between your feet and the ground.

56. To push a box across the floor takes more force than to push the same box on wheels across the floor. This shows that rolling friction is ____________________ (greater than, less than, equal to) sliding friction.

57. In order to keep a race car going around a circular track at constant speed, ____________________ (no force, a balanced force, an unbalanced force) is needed.

58. A reaction force is created ____________________ (before, after, at the same time as) its action force.

59. The force needed to accelerate a full-size car to a given velocity is ____________________ (greater than, less than, equal to) the force needed to accelerate a motorcycle to the same velocity.

60. The displacement of a car driving a winding road up a mountain is ____________________ (greater than, less than, the same as) the distance the car travels.

61. When you push off of the side of a swimming pool, the force of your foot on the wall is created ____________________ (before, after, at the same time as) the force of the wall on your foot.

62. When a ball starts to fall through the air, the force of air resistance on the ball is ____________________ (greater than, less than, the same as) the force of gravity.

63. The mass of an astronaut ____________________ (increases, decreases, remains the same) when the astronaut goes on a space walk.

64. A crumpled piece of paper falls to the ground faster than a smooth piece because of ____________________.

65. When you push a book across your desk, the force of your hand is ____________________ the force of static friction.

66. The force needed to accelerate a bowling ball to a given velocity is ____________________ the force needed to accelerate a soccer ball to the same velocity.

67. A radio-controlled plane flies 75 m north, then 95 m south. Its ____________________ is 20 m south.

68. A car that travels 200 km in 2 h has a(n) ____________________ speed of 100 km/h.

69. ____________________ keeps you from sliding backward when you climb a hill.

70. ____________________ is the tendency of a body to resist change in its motion.

71. Forces always occur in equal but opposite ____________________.

Matching

Match each item with the correct description below.
a.
static friction
k.
Unbalanced forces
b.
force
l.
Acceleration
c.
rolling friction
m.
Inertia
d.
displacement
n.
Speed
e.
first law of motion
o.
Second law of motion
f.
Newton’s laws of motion
p.
Friction
g.
Sliding friction
q.
Air resistance
h.
Velocity
r.
Mass
i.
Balanced forces
s.
Newton (N)
j.
Third law of motion
t.
weight


____ 72. the distance and direction between starting and ending positions

____ 73. the distance traveled divided by the time needed to travel the distance

____ 74. change in velocity divided by the amount of time required for the change to occur

____ 75. displacement divided by time

____ 76. an object will remain at rest or move in a straight line with constant speed unless it is acted upon by a force

____ 77. equal forces that move in opposite directions

____ 78. a push or a pull

____ 79. forces that move in opposite directions that are not of equal strength

____ 80. a force that resists motion

____ 81. an object acted upon by an unbalanced force will accelerate in the direction of the force

____ 82. forces always act in equal but opposite pairs

____ 83. Air molecules act on the forward-moving surface of an object, slowing its motion.

____ 84. the friction that occurs when two surfaces slide past each other

____ 85. the friction that hinders a stationary object from moving on a surface when a force is applied to that object

____ 86. a force that can change when acceleration due to gravity changes

____ 87. a measure of the amount of matter in an object

____ 88. measures an object’s tendency to remain at rest or keep moving with constant velocity

____ 89. used to measure force

____ 90. a set of rules used to predict and explain motion

____ 91. The type of friction that makes a tire turn and a ball roll is called ____.

Match the unit with the quantity it measures.
a.
second
d.
m/s2
b.
newton
e.
meter
c.
m/s



____ 92. speed

____ 93. distance

____ 94. force

____ 95. time

____ 96. acceleration

Match Newton’s laws of motion with the examples given.
a.
Newton’s first law
c.
Newton’s third law
b.
Newton’s second law



____ 97. A magician pulls the table cloth off a table, leaving the dishes on the table.

____ 98. A ball rolling across the floor eventually comes to a stop.

____ 99. A rower’s arms push the oars against the water. The boat moves forward after the water pushes against the oars.

____ 100. A rock moves slower when shot out of a slingshot than a pebble shot out of the same slingshot.

____ 101. You jump off a raft in the swimming pool, and when you turn around to get back on the raft, the raft has floated off in the opposite direction.

Short Answer

102.
If you run three laps around a circular race track at 5 m/s, what do you know about your speed, velocity, and acceleration?

103. A high speed train travels south for 2.00 h for a distance of 454 km. What is its average velocity?

104. Calculate the force necessary to accelerate a 0.14-kg hardball at a rate of 100 m/s2.

105. A car travels 528 km in six hours. Find its average speed.

106. Is it possible to have a single force? Explain why or why not.

107. It has been found that when a karate blow of a fist strikes a wooden block, the block can exert a force of 2,450 N on the hand. What force must be put on the block to break it?

108.
Explain the difference between speed and velocity.

109.
Mr. French’s class is using a toy car to study Newton’s laws of motion.

Part A What does Newton’s first law state?

Part B Give an example of how the class can use the toy car to demonstrate how the law works.

110.
Compare and contrast distance and displacement.

111.
Compare and contrast speed and velocity.

112.
Is it necessary for an object to be in motion if it has forces acting on it? Why or why not?

113.
"If no forces are acting on a moving object, it will eventually come to rest." Comment on this statement.

114.
If you were playing football on the space station, would it be as hard to stop a 150-kg lineman as it would be on Earth? Why or why not?

115.
How is force similar to displacement and velocity?

116.
You drop a pebble from a bridge and it goes faster and faster before it hits the water. What do you know about the forces acting on the pebble?

117.
If a body is in motion at constant speed in a straight line, what, if any, forces could be acting on it?

118.
How could you decrease the force a horse needed to pull a wagonload of hay?

119.
For a long time, all experiments showed that a force had to be applied to keep a body in motion at constant velocity. How does our knowledge of the force of friction help us to understand, now, that this isn't true?

Figure 23-1

120.
In Figure 23-1, identify two pairs of action-reaction forces involving the rope.

121.
In Figure 23-1, identify two balanced forces involving the rope.

122.
In Figure 23-1, if the black dog starts pulling on the rope harder than the white dog, what will happen to the rope?

123.
In Figure 23-1, how could the rope-on-black-dog force be increased?

124.
In Figure 23-1, if the rope moves toward the white dog, what do you know about the forces on the rope?

125.
If you throw a ball into the air, after it leaves your hand, what is/are the net force(s) acting on it? Describe the ball's acceleration.

126. A coasting car slows down from 27 m/s to 24 m/s in 6 s. What is the car’s acceleration?

127. The maximum acceleration of a fist in a karate punch is 3800 m/s2. The mass of the fist is 0.70 kg. If the fist hits a wooden block, what force does the wood place on the fist?

128. When a ball is dropped it is easy to see that Earth exerts a force on it. Why can’t you tell that the ball exerts a force on Earth?

129. If you and your friend ride bumper cars at the fair, what happens, in terms of Newton’s third law, when they collide?

130. If you bump into a heavy desk sitting on a carpet, it doesn’t move. Explain.

Problem

131.
A top-fuel dragster accelerates from rest to a velocity of 100 m/s in 8 s. What is the acceleration?

132.
On Planet Zorg, a 30-kg barbell can be lifted by only exerting a force of 180 N. What is the acceleration of gravity on Planet Zorg?

133.
A racing car has a mass of 750 kg. It undergoes an acceleration of 4.00 m/s2. What is the net force acting on the car?

134.
0.30 s after seeing a puff of smoke rise from the starter's pistol, the sound of the firing of the pistol is heard by the track timer 100 m away. What is the speed of sound?

Essay

135. An astronaut in the space shuttle turns a screwdriver clockwise. The astronaut starts to rotate in a counterclockwise direction. Why does this happen?

136. You are worried about a severe storm in your area. You hear a weather broadcast that says that the storm is moving at a speed of 25 km/h. Is this all you need to know for safety? Explain why or why not in terms of speed and velocity.

137. You ride three full turns around on a merry-go-round horse. What is your displacement? Your speed is constant; is your velocity constant? Why or why not?

138. A dog on a chain is fastened to the side of a house.
a. As the dog pulls on the end of the chain, name two pairs of action-reaction forces acting on the chain.
b. What are the balanced forces on the chain?
c. What happens to the forces on the chain if the dog pulls the chain away from the wall and runs to play?