Which of the following is not true if there's no net externaltorque on a system? A) The moment of inertia of the system can change B) The angular acceleration of the system is non-zeroand constant C) The system will rotate with constant angularvelocity D) If the moment of inertia of the system increases theangular speed should decrease Which of the following is not true if there's no net externaltorque on a system? A) The moment of inertia of the system can change B) The angular acceleration of the system is non-zeroand constant C) The system will rotate with constant angularvelocity D) If the moment of inertia of the system increases theangular speed should decrease
Explanation / Answer
Net external torque on the system is zero Since there isno external torque. Then from law of conservation of angular momentum , angularmomentum L = constant L = constant Iw = constant I 1/ w i.e, moment of inertia and angular speed are inverselyproportional. That means if the moment of inertia of the system increasesthe angular speed should decrease