cq_1_072

#$&*

Phy 121

Your 'cq_1_07.2' report has been received. Scroll down through the document to see any comments I might have inserted, and my final comment at the end.

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An automobile rolls 10 meters down a constant incline with slope .05 in 8 seconds, starting from rest. The same automobile requires 5 seconds to roll the same distance down an incline with slope .10, again starting from rest.

• At what average rate is the automobile's acceleration changing with respect to the slope of the incline?

answer/question/discussion: ->->->->->->->->->->->-> :

The acceleration increases from 0.315 m/s^2 to 0.8 m/s^2 when you increase the slope from .05 to 0.1. This means the average change in acceleration is (0.3125 m/s^2 + 0.8 m/s^2) / 2 =0.556 m/s^2

10 m

.05 slope

8 seconds

1.25 m/s average velocity

2.5 final velocity

2.5 / 8 = .3125 m/s2

10 m

.1 incline

5 second

2 m/s average velocity

4 m/s final velocity

4 / 5 = .8 m/s2

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30 minutes

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Good work on the accelerations.

That last rate of change question is seldom interpreted correctly on the first try. Do submit a revision on that part.

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Then please compare your solutions with the expanded discussion at the link

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