A CD player rotates at different speeds depending on where t

A CD player rotates at different speeds depending on where the laser is reading the disc. When the laser is at the edge of the CD with a diameter of 5.25 inches, the CD is rotating at 200 revolutions per minute. Find the angular velocity of the CD in radians per minute, and the linear speed of a point on the edge of the CD in miles per hour, rounded to the nearest tenth of a mile.

Please show work, because I\'d like to know how to do the problem, not just the answer.

Solution

radius dia/2 = 5.25/2 = 2.625 inch

anglular velocity in rad/min = revolution per min.*2pi = ( 200)*2pi = 1256.37 rad/min.

Linear speed = angular speed x radius =1256.37x 2.625 = 3298.67 inch/min

1inch/min = 0.00094697

So, Linear speed (mi/hr) = 3.12 = 3.1 miles/hr