cq_1_031

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phy 121

Your 'cq_1_03.1' 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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The problem:

A ball starts with velocity 0 and accelerates uniformly down a ramp of length 30 cm, covering the distance in 5 seconds.

What is its average velocity?

answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):

6 cm/s

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If the acceleration of the ball is uniform then its average velocity is equal to the average of its initial and final velocities.

You know its average velocity, and you know the initial velocity is zero.

What therefore must be the final velocity?

answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):

6=(x+0)/2

x= 12 cm/s

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By how much did its velocity therefore change?

answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):

It accelerated by 12 cm/s.

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At what average rate did its velocity change with respect to clock time?

answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):

12/5 cm/s

@& 12 / 5 is good, but you also need to include the units of 12 and the units of 5. When you do the units calculations, you will see that the final units are not cm/s. Still, you have the right idea here.*@

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What would a graph of its velocity vs. clock time look like? Give the best description you can.

answer/question/discussion: ->->->->->->->->->->->-> (start in the next line):

It increases at a constant rate with a fairly shallow slope.

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10 minutes

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&#See any notes I might have inserted into your document, and before looking at the link below see if you can modify your solutions. If there are no notes, this does not mean that your solution is completely correct.

Then please compare your old and new solutions with the expanded discussion at the link

Solution

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