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Question
A 5000-kg freight car crashes into a 10,000-kg freight car at rest. They couple upon collision and move with a speed of 2 m/s. What was the initial speed of the 5000-kg freight car?A) 4 m/s
B) 5 m/s
C) 6 m/s
D) 8 m/s
E) none of the above
Answer
This answer is hidden. It contains 1 characters.
Related questions
Q:
Which requires more energy?
A) melting a gram of 0C ice
B) increasing the temperature of 1 gram of water from 0C to 100C
C) changing 1 gram of 100C water to 100C steam
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In walking barefoot on red-hot coals, providing that bits of coal do not stick to your feet, it would be safer if your feet are
A) wet.
B) dry.
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B) and increases in temperature.
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When bringing water to a boil in the mountains, the time needed to reach the boiling point is
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Q:
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A) down.
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Q:
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A) good absorber of radiation.
B) good emitter of radiation.
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Q:
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Q:
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A) conduction.
B) convection.
C) radiation.
D) all about equally
Q:
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B) slows heat flow.
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B) transfers.
C) both of these
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Q:
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B) joules.
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D) both joules and calories.