cq_1_061

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PHY 201

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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Seed Questions 1_06.1 submitted 8 Feb 11 around 12:45 PM.

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15 mins

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Seed Questions 1_06.1

Copy the problem below into a text editor or word processor.

• This form accepts only text so a text editor such as Notepad is fine.

• You might prefer for your own reasons to use a word processor (for example the formatting features might help you organize your answer and explanations), but note that formatting will be lost when you submit your work through the form.

• If you use a word processor avoid using special characters or symbols, which would require more of your time to create and will not be represented correctly by the form.

• As you will see within the first few assignments, there is an easily-learned keyboard-based shorthand that doesn't look quite as pretty as word-processor symbols, but which gets the job done much more efficiently.

You should enter your answers using the text editor or word processor. You will then copy-and-paste it into the box below, and submit.

________________________________________

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: ->->->->->->->->->->->-> :

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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: ->->->->->->->->->->->-> :

vf = v0 + a * dt

v0 = vf – (a*dt)

v0 = 50 cm/s – (10 cm/s^2 * 3 s)

v0 = 50 cm/s – (30 cm/s)

v0 = 20 cm/s

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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 vf = 30 cm/s, v0 = 0cm/s and a= 20 cm/s^2

vf = v0 + a * dt

(vf –v0) = a * dt

dt = (vf – v0) / a

dt = (30 cm/s – 0 cm/s) / 20 cm/s^2

dt = 30 cm/s / 20 cm/s^2

dt = 1.5 sec

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Then for each situation answer the following:

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

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

Yes by using the formula vAve = (vf + v0) / 2

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• Is it possible to directly determine `dv?

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

Yes since we know the aAve and dt, then you will be able to find dv by using the formula aAve = dv / dt.

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@& Well done.*@