(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A solid disk with a radius of 1.4cm is a rest. The disk has 2.0m of string wound on to its circumference. The string is pulled off the disk by a constant force in a time of 7.3s. What is the final angular velocity of this disk?

2. Relevant equations

v = r*ω

3. The attempt at a solution

The correct answer is 39.1 rad/s but I keep getting half of that (19.6 rad/sec).

Since ω = v/r, I solve for v:

2m/7.3 sec = 0.274 m/s

then ω = (0.274 m/s)/(0.014 m) = 19.6.

what am I doing wrong? the correct answer is 39.1

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# Homework Help: Easy angular velocity question

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