Question

If the CD rotates clockwise at 500 {\rm rpm} (revolutions per minute) while the last song is playing, and then spins down to zero angular speed in 2.60 {\rms} with constant angular acceleration, what is \text type{\alpha }{alpha}, the magnitude of the angular acceleration of the CD, as it spins to a stop?

Answer 1

20138 rad/s2

Step-by-step explanation:

We can convert 500 revolution per minute to radians per second

`\omega = 500rev/min*2\pi rad/rev *(1)/(60)min/sec = 52.36 rad/s`

If the CD is coming to rest at a constant angular acceleration within 2.6 ms (or 0.0026s), this means:

`\alpha = (\delta\omega)/(\deltat) = (52.36 - 0)/(0.0026) = 20138 rad/s^2`