cq_1_051

#$&*

Phy 201

Your 'cq_1_05.1' 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 accelerates at 8 cm/s^2 for 3 seconds, starting with velocity 12 cm/s.

• What will be its velocity after the 3 seconds has elapsed?

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

8 cm/s2 x 3 sec = 24 cm/s3

#$&*

@& That's the change in velocity, but it's not the velocity the ball attains.*@

• Assuming that acceleration is constant, what will be its average velocity during this interval?

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

8 cm/s2 x 3 sec = 24 cm/s3

#$&*

@& It's very good that you're working with the units, and overall you're doing a good job with them.

However cm/s^2 * s = (cm/s^2) * (s / 1) = (cm * s) / s^2 = cm / s.

(cm/s^2) / s would be (cm/s^2) * (1/s) = cm/s^3, but that's not the calculation here.*@

• How far will it travel during this interval?

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

12 cm/s x 3 sec = 36 cm/s2

#$&*

@& 12 cm/s is the ball's initial velocity, but it's speeding up.

If it didn't speed up then it would travel 36 cm.

Note that cm/s * s = cm, not cm/s^2.*@

*#&!

@& A revision, and/or questions, would be in order here. You're on the right track, but you need to get a few details straight.*@