phy201
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:5.1
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: ->->->->->->->->->->->-> :
vf = v0 + a *'dt
vf = 12 cm/s + 8cm/s^2 * 3s
vf=60 cm/s
Right idea but you violated the order of operations: multiply before you add.
v0 + a * `dt means multiply a by `dt then add the result to v0.
vf = 12 cm/s + 8cm/s^2 * 3s means multiply 8 cm/s^2 by 3 s then add 12 cm/s.
It would be impossible to add 12 cm/s to 8 cm/s^2 in the first place, since they have different units and are hence unlike terms.
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Assuming that acceleration is constant, what will be its average velocity during this interval?
answer/question/discussion: ->->->->->->->->->->->-> :
vave= vf +v0 / 2
vave = (12cm/s + 60 cm/s) /2
vave = 36cm/s
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How far will it travel during this interval?
answer/question/discussion: ->->->->->->->->->->->-> :
'ds= ave change in velocity * 'dt
ds = 36cm/s * 3 s
ds = 108 cm
#$&*
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hour
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Very good, but see my note on the first part, where you violated the order of operations and therefore, even though you otherwise had all the right ideas, got the wrong answer.