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Question
Earth continually moves about 30 km/s through space, which means the wall you stand next to also is moving at 30 km/s. When you jump vertically the wall doesn't slam into you becauseA) the speeds of you and Earth cancel out.
B) you're moving horizontally just as fast as the wall.
C) your upward motion is small compared with Earth's speed.
D) motion of the Sun counteracts your motion.
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.
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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A) continue along the path as if the explosion didn't occur.
B) cancels to zero by vector addition.
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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.
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Q:
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Q:
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As the sloped surface supporting a shoe becomes steeper
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The force due to gravity that acts on a block of ice that slides down an icy ramp
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B) decreases as the slope of the ramp increases.
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Q:
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A) less than half her weight.
B) half her weight.
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Q:
When a cannonball is fired from a cannon, which undergoes the greater acceleration?
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Q:
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Q:
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Q:
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B) acceleration of the ball.
C) ball's pull on Earth.
D) none of the above
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.
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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
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B) force.
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