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.

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.

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?

7th Grade - Check this out on Ph

Here is the sight - when you enter you only have 5 minutes in each experiment - unless you sign up for the free 30 day trial.
http://www.explorelearning.com/index.cfm?method=cSearch.actDoSearch&NewSearch=1&uncompiledQuery=ph+analysis&Submit=GO

6th Grade Additional Test Prep - Chapter 14

Tables and Graphs
Directions: Match the information in Column I with the best way to display it from Column II. Write the letter of the correct term in the blank at the left. A letter may be used more than once.
Column I
Column II
a. bar graph b. circle graph c. line graph d. table
_____ 1. amount of rainfall in an area each month for a year_____
2. how the constellations change position over several hours_____
3. percents of the most abundant metals in Earth's crust_____
4. percents of the different gases in the atmosphere on Mars_____
5. daily high and low tide times for a week_____
6. how a sound wave travels through the air

Directions: Use the paragraph below to complete question 7.
Some animals can live much longer than others. For example, both the golden eagle and the blue whale have a maximum life span of more than 80 years, while a guppy's maximum life span is only five years. A giant spider may live 20 years, a lobster 50 years, and a crocodile may live 60 years.
Make a chart and draw a graph to display the data given in the paragraph.


What is science?
Directions: List the steps that are usually followed in scientific methods.
What does SI stand for?
Directions: Match each unit with what it measures by writing the correct letter in the space provided.
_____ 9. meter
a. length
_____ 10. liter
b. mass
_____ 11. kilogram
c. volume
Directions: Answer the following questions on the lines provided.
Suppose a scientist wants to test a new drug to fight the flu. The scientist injects the drug into three people with the flu. The scientist injects a harmless solution into three other people with the flu. In this experiment, what is the variable group and what is the control group?
Why is it necessary to follow safety rules in the science laboratory?
What is the difference between a theory and a scientific law?

6th Grade Reveiw test

This is NOT the test, but only a practice guide to help students identify areas that need more study time. The questions below are not on the TEST and do not cover ALL topics on the test.

Measurement
I. Testing Concepts
Directions: completes each statement or answers the question.
1. A pitcher holds 1.725 L. What is the capacity of the pitcher to the nearest liter?
2. Which unit would you use to measure the length of a mailbox?
3. The temperature on a spring day is 18°C. To the nearest whole number, what is the temperature in kelvins?
4. A scale is marked in tenths of a kilogram. To what precision can the mass of a bag of apples be measured?
5. Which of the following is NOT a measurement?
6. Which multiplier would you use to convert 1.9 km to meters?
7 Which unit would you use to measure the distance from Dallas, Texas, to Memphis, Tennessee?
8. Suppose you traveled to Mars. Compare your weight and your mass on Mars to your weight and mass on Earth.
a. Both your weight and mass would remain the same.b. Your weight would remain the same, your mass would change.c. Your weight would change, your mass would remain the same.d. Both your weight and your mass would change.
9. A digital thermometer shows the temperature as 21.2°C. The thermometer is precise to the nearest ______.
10. What property of an object is measured in grams?
11. A section of a circle graph measures 180°. What percent of a circle graph is this section?
12. What unit would you use to measure the area of a carpet?
13. Which graph would best show what percent of your class wears glasses?
14. Data in a table is organized ______.
15. What unit would you use to measure the length of a carpet?
16. Which is a reasonable estimate of the length around your wrist?
17. Which is the symbol for the SI unit of temperature?
18. How would you calculate the angle to show 20% in a circle graph?
19. Which is NOT an SI unit?
II. Understanding Concepts
Skill: Making and Using a Table
Create a Circle graph using the below numbers
1. Adult females
15
2. Adult males
12
3. Juvenile females
18
4. Juvenile males
15
Skill: Graphing
Use the angles from the table and your estimation skills to sketch a circle graph.
Suppose you want to graph the number of each type of sparrow. What kind of graph would you use?
III. Applying Concepts
Directions: Answer the following questions.
Explain how you would round 2.625 m to the nearest tenth of a meter.
How many centimeter cubes can be shipped in this box?
List these masses in order from greatest to least: 6471 mg, 9 kg, 76 mg, 422 g.
IV. Writing Skills
Directions: Answer the following questions using complete sentences.
How could you estimate a cat's length if you did not have a ruler?
Jenny says she can identify an SI base unit because a base unit does not contain a prefix. Is she right?

7th Grade - Chapter 3 Practice Test

This Practice test is solely to aid students. These are not the actual test questions but simialr questions that will help the students practice.

Inside the Atom
I. Testing Concepts
Directions: For each of the following, complete the sentence.
1. ______ contain(s) only one kind of atom.
2. A(n) ______ is the basic unit of matter.
3. Particles in an atom's nucleus that do not have an electric charge are called ______.
4. The atomic mass of an atom consists of the mass of the ______.
5. In an atom, the electrons can be found in the ______.
6. J. J. Thomson used the fact that ______ charges attract each other in his cathode-ray tube experiment.
7. The mass number of an isotope is the number of ______.
8. Isotopes are atoms of the same element that have a different number of ______.
9. To find the number of neutrons in an isotope, subtract the______.
a. atomic number from the mass numberb. mass number from the atomic numberc. number of isotopes from the mass numberd. number of protons from the number of electrons
_______ 10. The most stable isotope of an atom with 12 protons probably has ______ neutrons.
11. The strong nuclear force holds the ______ together.
12. Radioactive decay is the release of ______.
13. A(n) ______ particle consists of two protons and two neutrons.
14. The changing of one element into another in radioactive decay is called ______.
15. Radioactive decay can be affected by ______.
16. A radioactive isotope has a half-life of 100 years. A sample of 40 g of the isotope will have a mass of ______ g in 200 years.
17. Tracer elements can be used without danger to people because they have ______ halflives.
Directions: Identify each statement as true or false. Rewrite false statements to make them correct.
18. A proton is a positively charged particle present in the nucleus of all atoms.
19. The mass of a proton is much greater than the mass of a neutron.
20. Atoms of the same element can have a different number of neutrons.
21. Dalton believed that the atom was a hard sphere that was the same throughout.
22. J. J. Thomson did experiments that showed that atoms cannot be divided into smaller particles.
23. Rutherford's experiment showed that alpha particles could pass through foil because most of an atom is neutrally charged.
24. The strong nuclear force can hold the protons of an atom together only if the protons are far apart.
25. Once a living organism dies, the amount of carbon-14 cannot be replaced.
II. Understanding Concepts
Skill: Outlining
Directions: Answer the following questions on the lines provided.
In an outline, the subtopics are neutron, proton, and electron. What is the main topic?
In an outline, the subtopics are fossil dating, cancer detection, and circulation problems. What is the main topic?
III. Applying Concepts
Directions: Do the following calculation. Show your work in the space provided.
An atom has a mass number of 53 and an atomic number of 26. How many neutrons does it have? Include a formula that explains your calculation.
The isotopes of carbon (carbon-12, carbon-13, and carbon-14) have different mass numbers. Each isotope has six protons. Explain how you can determine the number of neutrons in each isotope.
A certain element has a half-life of 20 years. A scientist starts with 100 g of the element.
How many grams remain after 20 years?
How many grams remain after 40 years?
How many half-lives are there in a 100-year span? How many grams of the sample would remain at the end of the 100 years?
IV. Writing Skills
Directions: Answer the following question in complete sentences.
How is americium-241 used in smoke detectors?

7th Grade - Chapter 3 Study Sheet

This sheet does not contain all items on the test. It is just a quick review sheet that should help you target in on the areas you need to study more.

The Nucleus
Directions: Answer the following questions on the lines provided.
What does the atomic number of an element refer to?
Define isotopes. ________________________________________________________________
What is the strong nuclear force? __________________________________________________
Name two types of transmutations. _________________________________________________
Explain what happens during transmutation. __________________________________________
What is radioactive decay?
Describe an alpha particle.
Describe a beta particle.
What is meant by the half-life of a radioactive isotope?
Why are nuclear waste products a problem?
Why are tracer elements important?
Directions: Identify each statement as true or false. Rewrite the false statements to make them correct.
Radioactive isotopes used for medical purposes should have long half-lives.
Scientists can use particle accelerators to create new elements.
Archaeologists can estimate the age of any ancient artifact with carbon dating.
The half-life of a radioactive isotope decreases as the isotope decays.

Welcome Back!

I hope you all enjoy your very own class blog. Please be sure to complete the information sheet I will be handing out to all of you and fill it out completely.

Please direct all emails to me to: Hadleyjt@dadeschools.net. Do not email me at Gmail- I only use this account in order to run this blog.

See you tomorrow!

Creating a Lab Write-up

HOW TO CREATE A
LAB WRITE UP

Your Name
The Date
Your Period
Mrs. Portu-Hadley


Place Lab Title Here
(skip a line)
Material:
(list all materials)
(list all materials)
(skip a line)

Procedures:
List step 1
List step 2
List step 3
etc.
(skip a line)
Saftey precautions:
(Any symbols list the meaning ex. a picture of goggles means you need to wear goggles - you would write "wear goggles")
(skip a line)
Hypothesis:
If (what is going to be done in the experiment)..... then (what you think is going to be the outcome).
(skip a line)

Data and Observations:
(Data Table written in here)
(skip a line)
Analysis and conclusions:
(this is where you answer all of the books questions) and
(write about the outcome of the experiment and its effects on the world as well as how you would do the experiment better next time.)

7th Grade Lab List

1. Measuring Using Tools (pg 5)
2. Form and Function (pg 9)
3. Foiled (pg 12)
4. Kleenex Comparison
5. Red Cabbage
6. Boiling Broth