A solid cylinder of mass 20 kg rotates about its axis with angular speed 100 rad/s. The radius of the cylinder is 0.25 m. The kinetic energy associated with the rotation of the cylinder is

Options

A. 3025 J
B. 3225 J
C. 3250 J
D. 3125 J

Answer

D

Explanation

Kinetic energy of rotation = `(1)/(2) I omega^(2)`
`= (1)/(2) xx ((1)/(2) MR^(2)) omega^(2) = (1)/(4) xx 20 xx (0.25)^(2) xx 100 xx 100 = 3125 J`