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Lyrx [107]
2 years ago
11

Students were discussing a problem in which the class was asked to find the acceleration of a cart rolling up and down an inclin

e at the instant the cart was at the very top of its path. Malia says, At the top the velocity has to be zero so the acceleration has to be zero too. Sasha disagrees saying, No, the velocity is changing at the top so the acceleration cant be zero. Who do you agree with? Discuss the reason for your answer and explain why the one who is wrong might legitimately be confused about which answer is correct.
Physics
1 answer:
velikii [3]2 years ago
4 0

Sasha is correct: No, the velocity is changing at the top so the acceleration cant be zero.

Explanation:

The acceleration of an object is equal to the rate of change in velocity of the object:

a=\frac{\Delta v}{\Delta t} (1)

where

\Delta v is the change in velocity

\Delta t is the time interval

For the cart on the ramp, as the cart reaches the top of the ramp, its velocity becomes temporarily zero:

v = 0

This is the origin of Malia's mistake.

However, this only lasts a moment; in reality, its velocity is changing, in particular its direction is changing (from upward to downward).

As we can see from eq.(1), a non-zero change in velocity implies a non-zero acceleration. Therefore, Sasha is right, since the cart has a non-zero acceleration.

Learn more about acceleration:

brainly.com/question/11411375

brainly.com/question/1971321

brainly.com/question/2286502

brainly.com/question/2562700

#LearnwithBrainly

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Answer:

E=88200\ J

Explanation:

Given:

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<u>So, the energy dissipated during the skidding of car:</u>

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Answer:

Explanation:

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Now is a good time to review the Law of Conservation of Energy:

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