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?
v = r*ω
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