At a certain instant,a compact disc is rotating at 210 rpm.What is its angular speed in rad/s?
A)11 rad/s
B)22 rad/s
C)45 rad/s
D)69 rad/s
E)660 rad/s

Question

Quizplus · Accepted Answer

To convert revolutions per minute (rpm) to radians per second (rad/s), use the conversion factor $2\pi$ rad/rev and the fact that there are 60 seconds in a minute. Thus, $210 \, \text{rpm} = 210 \times \frac{2\pi}{60} \, \text{rad/s} = 22 \, \text{rad/s}$.

At a Certain Instant,a Compact Disc Is Rotating at 210