Question

A net torque of magnitude 200 Nm is exerted
on the rotor of an electric generator for 31 s.
What is the magnitude of the angular mo-
mentum of the rotor at the end of 31 s if it
was initially at rest?
Answer in units of kgm2/s

Answer 1

are you given the radius ?

Answer 2

Nope

Answer 3

torque=dL/dt. torque*time=change in angular momentum (if torque is constant); thus the answer is 200*31 N*m*s. 1 N=1 kg*m/s^2; 1 N*m*s=1 kg*m^2/s.
=200*31 kg*m^2/s

Answer 4

Thank you :)