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Question
If Earth had a pair of identical moons on opposite sides of the same circular orbit, the center of gravity of the double-moon-Earth system would beA) inside the Earth, but off center.
B) at the center of the Earth.
C) outside the Earth, but within the orbital path of the moons.
D) outside the Earth, but beyond the orbital path of the moons.
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
A) one-eighth as far.
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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If a Ping-Pong ball and a golf ball both move in the same direction with the same amount of kinetic energy, the speed of the Ping-Pong ball must be
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A cannonball following a parabolic path explodes into fragments. The momentum of the fragments
A) continue along the path as if the explosion didn't occur.
B) cancels to zero by vector addition.
C) both of these
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Q:
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C) 1 unit.
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Q:
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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Q:
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Q:
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Q:
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Q:
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B) 2,000 kg m/s.
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Q:
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A) 4 kg.
B) 12 kg.
C) 16 kg.
D) 144 kg.
E) none of these
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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C) four times as much.
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Q:
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D) nowhere"it can't be done.
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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.
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Q:
The force due to gravity that acts on a block of ice that slides down an icy ramp
A) remains equal to mg at all angles.
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Q:
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A) less than half her weight.
B) half her weight.
C) more than half her weight.
D) her weight.
Q:
When a cannonball is fired from a cannon, which undergoes the greater acceleration?
A) the cannonball
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C) both the same
Q:
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B) lighter car.
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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:
As a ball falls, the action force is the Earth's pull on the ball. The reaction force is the
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.
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
A) speed.
B) force.
C) both of these
D) neither of these