True/False
Indicate whether the statement is true or
false.
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1.
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The rotational speed of a wheel is defined as the number of rotations it makes
in a unit of time.
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2.
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When you whirl a can on the end of a string, the centripetal force on the can is
actually the pull of the string on the can.
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3.
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When an object turns about an external axis, the motion is called
rotation.
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4.
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Any force that causes an object to move in a circular path is called a
centripetal force.
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5.
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A bug on a turning phonograph record will make more turns per minute if it is
located toward the center of the record.
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Multiple ChoiceIdentify the choice that best completes the
statement or answers the question.
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6.
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If you whirl a tin can on the end of a string and the string suddenly breaks,
the can will
a. | fly off, tangent to its circular path. | b. | fly directly toward you. | c. | spiral in toward
your hand. | d. | spiral away from your hand. | e. | fly directly away from
you. |
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7.
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A tin can whirled on the end of a string moves in a circle because
a. | there is an inward force acting on the can. | b. | there is a force on
the can pulling it outward. | c. | once the can starts moving, that is its natural
tendency. | d. | the can continually pulls on the string. | e. | all of the
above |
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8.
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A car travels in a circle with constant speed. The net force on the car
a. | is directed toward the center of the curve. | b. | is zero because the
car is not accelerating. | c. | is directed forward, in the direction of
travel. | d. | none of the above |
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9.
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What is the centripetal acceleration on the can in this diagram below if
the radius of the circle was 2.0 meters, and the velocity was 5.0
m/s?  a. | 125 m/s2 | c. | 2.5 m/s2 | b. | 12.5 m/s2 | d. | 25
m/s2 |
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10.
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What is the net force on the 0.30 kg ball in this example
if the centripetal acceleration was 50.0 m/s2?  a. | 30 N | c. | 150 N | b. | 0.006 N | d. | 15 N |
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11.
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The tangential speed at the outer rim of a Ferris wheel is 20 m/s. What
is the tangential speed of a position half way from the center to the outer rim?
a. | 20 m/s | c. | 5 m/s | b. | 10 m/s | d. | 8 m/s |
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12.
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You sit at the outer rim of a Ferris wheel that rotates at 6 revolutions per
minute (RPM). What would your rotational speed be if you were instead clinging to a position halfway
from the center to the outer rim?
a. | 3 RPM | c. | 6 RPM | b. | 12 RPM | d. | 4 RPM |
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13.
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A vertical pole standing against a wall topples to the ground and the center of
the pole has a speed of 10 m/s as it hits. With what speed does the far end of the pole hit the
ground?
a. | 20 m/s | c. | 100 m/s | b. | 10 m/s | d. | 5 m/s |
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14.
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You are sitting on a merry-go-round and the outer edge 2 meters from the
center and have a tangential speed of 4 m/s. What is your centripetal
acceleration (ac)?
a. | 4 m/s2 | c. | 2 m/s2 | b. | 8 m/s2 | d. | 6
m/s2 |
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15.
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The tangential speed at the outer rim of a Ferris wheel is 8 m/s. What is
the tangential speed of a position half way from the center to the outer rim?
a. | 2 m/s | c. | 8 m/s | b. | 16 m/s | d. | 4 m/s |
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16.
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You are driving in a 1000 kg car around a circular path at a constant
speed of 1 m/s. The track has a radius of 20 meters. What is the
centripetal force acting on the car?
a. | 2000 N | c. | 50 N | b. | 1000 N | d. | 100 N |
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17.
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Which has greater linear speed, a horse near the outside rail of a
merry-go-round or a horse near the inside rail?
a. | Neither—they both have the same linear speed. | b. | The outside
horse | c. | The inside horse |
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18.
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A ball on a rope swings around a vertical pole. In which direction will
the ball fly if released at the location
shown?
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