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DIA [1.3K]
3 years ago
11

A train is moving in the positive direction down a track. First the train speeds up, and then it slows down. What is its acceler

ation?
A. The train has positive acceleration throughout.
B.The train has negative acceleration throughout.
C.The train first has positive acceleration and then negative acceleration.
D.The train first has negative acceleration and then positive acceleration.
Physics
2 answers:
tatuchka [14]3 years ago
8 0
C.

The train first sped up, giving it a positive acceleration in the beginning. This eliminates D since that choice states that it begins with a negative acceleration. This also eliminates B since that choice states that the train only had a negation acceleration.

Next, the train slows down, giving it a negative acceleration. We’re looking for the answer choice that starts with a positive acceleration and ends with a negative one. This makes C the correct answer. Hope this helps!
Marina86 [1]3 years ago
8 0

Answer:

The answer is <u><em>The train first has positive acceleration and then negative acceleration. </em></u>

<u><em></em></u>

Explanation: I answered the question right on my online school quiz.

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A teacher discusses a scientific theory that has been in place for almost a century. which would present the greatest challenge
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Answer: The theory might have become Obsolete or Superseded

Explanation:

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Answer:

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3 years ago
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3 years ago
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What is the frequency heard by a person driving at 15 m/s toward a factory whistle emitting a
zmey [24]

Answer:

835.29 Hz

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