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.