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Question
Although solid matter is mostly empty space, we don't fall through the floor becauseA) atoms are constantly vibrating, even at absolute zero.
B) of nuclear forces.
C) of gravitational forces.
D) of electrical forces.
E) none of the above
Answer
This answer is hidden. It contains 1 characters.
Related questions
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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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Q:
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Q:
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Q:
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A) momentum.
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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:
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.
D) all of the above
E) none of the above
Q:
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A) remains equal to mg at all angles.
B) decreases as the slope of the ramp increases.
C) becomes greatest when the ramp is vertical.
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
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
A) heavier car.
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:
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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.
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
A) combined weight of the arrow and bowstring.
B) friction of the ground against the archer's feet.
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Q:
A fast-moving missile soaring overhead possesses
A) speed.
B) force.
C) both of these
D) neither of these