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Question
The power expended doing 100 J of work in 50 s isA) 1/2 W.
B) 2 W.
C) 4 W.
D) 50 W.
E) 5,000 W.
Answer
This answer is hidden. It contains 1 characters.
Related questions
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B) one-fourth as far.
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Q:
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A) is more concentrated.
B) meets less resistance than the cannon on the ground.
C) acts over a longer distance.
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A golf ball moving forward with 1 unit of momentum strikes and bounces backward off a heavy bowling ball that is initially at rest and free to move. The bowling ball is set in motion with a momentum of
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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:
Padded dashboards in cars are safer in an accident than non-padded ones because passengers hitting the dashboard encounter
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Q:
It is correct to say that impulse is equal to
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Q:
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A) 4 kg.
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.
E) none of the above
Q:
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A) zero.
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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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Q:
As the sloped surface supporting a shoe becomes steeper
A) the shoe's weight mg remains unchanged.
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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C) more 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
C) both the same
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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A) air resistance acting against the ball.
B) acceleration of the ball.
C) ball's pull on Earth.
D) none of the above
Q:
To produce an acceleration to a system there
A) must be a net force on the system.
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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
A) speed.
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