Torque on a uniform disk of mass 2 kg, radius 1 m is given as τ(t) = 5t^2 - 8t.

Question

Torque on a uniform disk of mass 2 kg, radius 1 m is given as \(\tau(t) = 5t^2 -8t\). If the disk was initially at rest, find power by torque at t = 1s.

(1) 5 W

(2) 3 W

(3) 7 W

(4) 9 W

Answer 1

Correct option is : (3) 7 W

\(\rho = \vec t\ .\ \vec \omega\)

\(\tau =I\alpha\)

\(I = \frac{MR^2}{2} = 1\)