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Question
If the sky were ordinarily yellow-orange instead of blue, then sunsets would appear1) orange,
2) green,
3) blue,
4) black,
which has to do with
5) the polarization of sunlight.
6) yellow-orange and sky blue being complementary colors.
7) the refraction of sunlight through the thicker atmosphere.
Answer
This answer is hidden. It contains 3 characters.
Related questions
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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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A) continue along the path as if the explosion didn't occur.
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B) 2,000 kg m/s.
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Q:
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B) 12 kg.
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E) none of these
Q:
The speed of a 4-kg ball with a momentum of 12 kg m/s is
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Q:
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D) nowhere"it can't be done.
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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?
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B) lighter car.
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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
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B) force.
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