cq_1_061

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PHY 241

Your 'cq_1_06.1' 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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For each situation state which of the five quantities v0, vf, `ds, `dt and a are given, and give the value of each.

• A ball accelerates uniformly from 10 cm/s to 20 cm/s while traveling 45 cm.

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

Given quantities: v0, vf, ‘ds.

V0 = 10 cm/s, vf = 20 cm/s, ‘ds = 45cm.

It is possible to directly determine vAve. Do (v0 + vf) / 2 to determine it.

It is possible to directly determine ‘dv. Do (vf – v0) to determine it.

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• A ball accelerates uniformly at 10 cm/s^2 for 3 seconds, and at the end of this interval is moving at 50 cm/s.

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

Given quantities: a, ‘dt, vf.

A = 10 cm/s^2, ‘dt = 3 sec, vf = 50 cm/s.

It is not possible to DIRECTLY determine vAve, though it can be found through steps. Since we have a and ‘dt we can use the equation a = ‘dv / ‘dt to find that 10 cm/s^2 = ‘dv / 3 seconds. Multiplying by 3 on both sides gives us ‘dv = 30 cm/s. Since ‘dv = vf – v0, and we know vf to be 50 cm/s, we see that 30 cm/s = 50 cm/s – v0. Thus, v0 would equal 20 cm/s.

It is possible to directly determine ‘dv. I found it in the previous step, actually.

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• A ball travels 30 cm along an incline, starting from rest, while accelerating at 20 cm/s^2.

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

Given quantities: ‘ds, v0, a.

‘ds = 30cm, v0 = 0 cm/s, a = 20 cm/s^2.

It is not possible to directly determine vAve.

It is not possible to directly determine ‘dv.

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Then for each situation answer the following:

• Is it possible from this information to directly determine vAve?

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

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• Is it possible to directly determine `dv?

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

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10 minutes.

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November 1. 12:08

&#Very good work. Let me know if you have questions. &#