Question

A CD has to rotate under the readout-laser with a constant linear velocity of 1.25 m/s. If the laser is at a position 3.7 cm from the center of the disk, what are the revolutions per minute (rpms) of the disk?

Answer 1

Answer:N=322.53 rpm

Step-by-step explanation:

Given

Linear velocity (v)=1.25 m/s

Position from center is 3.7 cm

we know

`v=\omega * r`

`1.25* 100=\omega * 3.7`

`\omega =(125)/(3.7)=33.78`

and
`(2\pi N)/(60)=\omega`

`N=(\omega * 60)/(2\pi )`

`N=(33.78* 60)/(2\pi )`

N=322.53 rpm