cq_1_051

Phy 121

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: v = v0 + at = 12cm/s + 8cm/s^2 * 3s = 36cm/s

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

answer/question/discussion: 36cm/s + 12cm/s / 2 =18cm/s

36cm/s + 12cm/s / 2 = 36 cm/s + 6 cm/s = 42 cm/s, but you meant

(36cm/s + 12cm/s) / 2. That comes out 24 cm/s, not 18 cm/s.

That affects your next answer, but it's clear you understand the process.

How far will it travel during this interval?

answer/question/discussion: `ds = vAve * dt = 18cm/s * 3s = 54cm

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15min

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Other than a simple error in arithmetic, you did fine. No need to revise, but be sure to see my notes.