I think this is a simple question but I'm not sure if I'm doing it right, this is what I have so far...(adsbygoogle = window.adsbygoogle || []).push({});

A watch has a second hand 2.0 cm long.

a) Compute the speed of the tip of the second hand.

C = 2pi(r) r = 2.0cm = 0.02m - leave as cm or convert to m?

V = [2pi(0.02m)]/60s = 2.1 x 10^-3 m/s - divide by 60s? :uhh:

b) What is the velocity of the tip of the second hand at 0.0s ? At 15 seconds?

well 0s=60s right...? if so then the answer is the same as a)

for 15s V=[2pi(0.02m)]/15s = 8.3 x 10^-3 m/s

c) Compute its change in velocity between 0.0 and 15 seconds.

?

d) Compute its average vector acceleration between 0.0 and 15 seconds.

I think I could answer this if I could figure out c)

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# Homework Help: Compute the speed of the tip of the second hand

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