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Question
What was discovered in atomic spectra by physics pioneers Balmer, Rydberg, and Ritz?A) unexplained randomness
B) mathematical order
C) all atoms are about the same size
D) electrons occupy well-defined shells about the atomic nucleus
E) electrons behave as standing waves
Answer
This answer is hidden. It contains 1 characters.
Related questions
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If the speed of a bicycle is reduced to half before skidding to a stop, it will skid
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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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If a Ping-Pong ball and a golf ball both move in the same direction with the same amount of kinetic energy, the speed of the Ping-Pong ball must be
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A cannonball following a parabolic path explodes into fragments. The momentum of the fragments
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B) cancels to zero by vector addition.
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A golf ball moving forward with 1 unit of momentum strikes and bounces backward off a heavy bowling ball that is initially at rest and free to move. The bowling ball is set in motion with a momentum of
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A fan attached to an ice sailcraft stalled on a windless day blows air into the sail that bounces backward upon impact. The boat
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Q:
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Q:
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Q:
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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.
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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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As the sloped surface supporting a shoe becomes steeper
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The force due to gravity that acts on a block of ice that slides down an icy ramp
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A) less than half her weight.
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Q:
When a cannonball is fired from a cannon, which undergoes the greater acceleration?
A) the cannonball
B) the recoiling cannon
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Q:
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A) somewhat greater than Moon's pull on Earth.
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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.
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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
A) speed.
B) force.
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D) neither of these