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Question
If a child swinging to and fro on a playground swing stands up, her time for a to-and-fro swing isA) longer.
B) shorter.
C) unchanged.
Answer
This answer is hidden. It contains 1 characters.
Related questions
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If the speed of a bicycle is reduced to half before skidding to a stop, it will skid
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B) one-fourth as far.
C) one-half as far.
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Q:
A cannonball has more kinetic energy than the recoiling cannon from which it is fired because the force on the ball
A) is more concentrated.
B) meets less resistance than the cannon on the ground.
C) acts over a longer distance.
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When you jump from an elevated position you usually bend your knees upon reaching the ground, which makes the time of the contact about 10 times that of a stiff-legged landing. In this way the average force your body experiences is
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Q:
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Q:
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B) 12 kg.
C) 16 kg.
D) 144 kg.
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Q:
The speed of a 4-kg ball with a momentum of 12 kg m/s is
A) 3 m/s.
B) 4 m/s.
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D) 48 m/s.
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Q:
A river 100 m wide flows due south at 1 m/s. A boat that goes 1 m/s relative to the water leaves the west bank. To land at a point due east of its starting point, the boat must be pointed
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As the sloped surface supporting a shoe becomes steeper
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A) less than half her weight.
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Q:
When a cannonball is fired from a cannon, which undergoes the greater acceleration?
A) the cannonball
B) the recoiling cannon
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Q:
A pair of toy freight cars, one twice the mass of the other, fly apart when a compressed spring that joins them is released. Acceleration will be greater for the
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Q:
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A) somewhat greater than Moon's pull on Earth.
B) the only force acting between Earth and Moon.
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Q:
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B) acceleration of the ball.
C) ball's pull on Earth.
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Q:
To produce an acceleration to a system there
A) must be a net force on the system.
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Q:
An archer shoots an arrow. Consider the action force to be the bowstring against the arrow. The reaction to this force is the
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Q:
A fast-moving missile soaring overhead possesses
A) speed.
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