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Question
Ice has a lower density than water because iceA) molecules are more compact in the solid state.
B) molecules vibrate at lower rates than water molecules.
C) is composed of open-structured crystals.
D) density decreases with decreasing temperature.
Answer
This answer is hidden. It contains 1 characters.
Related questions
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Q:
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Q:
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Q:
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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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Q:
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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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D) nowhere"it can't be done.
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As the sloped surface supporting a shoe becomes steeper
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C) friction needed to keep it at rest increases.
D) all of the above
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Q:
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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.
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
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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:
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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.
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Q:
A fast-moving missile soaring overhead possesses
A) speed.
B) force.
C) both of these
D) neither of these