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Once the child in the sample problem reaches the bottom of the hill, she continues sliding along the flat, snow-covered ground until she comes to a stop. If her acceleration during this time is -.392m/s^2 how long does it take her to travel from the bottom of the hill to her stopping point

User Berline
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Sample problem is;

A child slides down a steep, snow covered hill with an acceleration of 2.82 m/s². Her initial speed is 0.0 m/s² and her final speed is 15.5 m/s travelling from top to bottom of the hill.

Answer:

t = 39.54 s

Explanation:

We are told that her acceleration is now -0.392 m/s²

Thus; a = -0.392 m/s²

From the sample problem, we have;. Initial velocity = 0 m/s

Final velocity = 15.5 m/s

However, in this question, we want to find the time from the bottom of the hill to her stopping point.

This means her initial velocity will now be; u = 15.5 m/s and final velocity since she will come to rest will be v = 0 m/s

To find the time it takes her to travel from the bottom of the hill to her stopping point, we will use Newton's equation of motion and so, we have;

v = u + at

making t the subject, we have;

t = (v - u)/a

t = (0 - 15.5)/(-0.392)

t = 39.54 s

User Louis Carrese
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