A) \[\frac{3\,J}{5}\]
B) \[\frac{4\,J}{5}\]
C) \[\frac{5\,J}{4}\]
D) none of these
Correct Answer: B
Solution :
Key Idea: Torque is defined as rate of change of angular momentum. We know that rate of change of angular momentum (J) of a body is equal to the external torque (r) acting upon the body. i.e., \[\frac{d\,J}{dt}=\tau \] Given, \[{{J}_{1}}=J,\,\,{{J}_{2}}=5\,J\] \[\therefore \] \[\Delta \,J={{J}_{2}}-{{J}_{1}}=5\,J-J=4\,J\] Hence, \[\tau =\frac{4}{5}J\]
You need to login to perform this action.
You will be redirected in
3 sec
