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Question
A 50-N object falling in air experiences 30 N of air resistance. The net force on the falling object isA) 0 N.
B) 20 N.
C) 50 N.
D) 80 N.
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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Q:
As a block of ice at 0C melts, the block absorbs energy
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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:
A good cook knows that the temperature of violently boiling water is
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Q:
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Long ago a runaway greenhouse effect greatly transformed the planet
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Q:
When you leave your warm house for an hour or so on a cold day, to save energy you should turn the thermostat
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Q:
A good reflector of radiation is a
A) good absorber of radiation.
B) good emitter of radiation.
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Q:
A piece of pizza is normally a net radiator of energy when its temperature is
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Q:
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A) still warm.
B) cool.
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Q:
Coastal winds that shift from night to day illustrate
A) conduction.
B) convection.
C) radiation.
D) all about equally
Q:
A water-filled paper cup held in a flame will not catch fire because
A) the inside of the paper is wet.
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Q:
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Q:
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B) a tent.
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Q:
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Q:
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B) slows heat flow.
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Q:
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A) calories.
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Q:
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A) contains.
B) transfers.
C) both of these
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Q:
Heat energy is measured in units of
A) degrees.
B) joules.
C) calories.
D) both joules and calories.