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Question
Two identical particles move toward each other, one twice as fast as the other. Just before they collide, one has a kinetic energy of 25 J and the other 50 J. At this instant their total kinetic energy isA) 25 J.
B) 50 J.
C) 75 J.
D) none of the above
E) need more information
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.
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D) none of the above
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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Q:
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B) cancels to zero by vector addition.
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A fan attached to an ice sailcraft stalled on a windless day blows air into the sail that bounces backward upon impact. The boat
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Q:
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A) less than 1/10 as great.
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Q:
Padded dashboards in cars are safer in an accident than non-padded ones because passengers hitting the dashboard encounter
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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:
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A) zero.
B) twice.
C) four times as much.
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Q:
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Q:
As the sloped surface supporting a shoe becomes steeper
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B) the normal force becomes less.
C) friction needed to keep it at rest increases.
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Q:
The force due to gravity that acts on a block of ice that slides down an icy ramp
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Q:
When Nellie hangs suspended from a pair of ropes that are not vertical, the tension in each rope is
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
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B) lighter car.
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A) somewhat greater than Moon's pull on Earth.
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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:
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A) must be a net force on the system.
B) may or may not be a net force on the system.
C) must be acceleration outside the system also.
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
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