When the play button is pressed, a cd accelerates uniformly from rest to 450 rev/min in 3.0 revolutions. if the cd has a radius of 7.0 cm and a mass of 17 g , what is the torque exerted on it? express your answer using two significant figures.

To solve this problem it is necessary to apply the kinematic equations of angular motion.

Torque from the rotational movement is defined as

where

I = Moment of inertia For a disk

Angular acceleration

The angular acceleration at the same time can be defined as function of angular velocity and angular displacement (Without considering time) through the expression:

Where

Final and Initial Angular velocity

Angular acceleration

Angular displacement

Our values are given as

Using the expression of angular acceleration we can find the to then find the torque, that is,

With the expression of the acceleration found it is now necessary to replace it on the torque equation and the respective moment of inertia for the disk, so

Therefore the torque exerted on it is

a.) is the correct answer.

explanation: