A constant external torque `tau` acts for a very brief period `/_\t` on a rotating system having moment of inertia `I` then

A constant external torque tau acts for a very brief period Delta t on a rotating system having moment of inertia I . ( i ) The angular momentum of the system will change by tau Delta t ( ii ) The angular velocity of the system will change by (tau Delta t)//I . ( iii ) If the system was initially at rest, it will acquire rotational kinetic energy (tau Delta t)^(2)//2I . ( iv ) The kinetic energy of the system will change by (tau Delta t)^(2) I .

Two particle are initially moving with angular momentum vec(L)_(1) and vec(L)_(2) in a region of space with no external torque. A constant external torque vec( tau) then acts on one particle, but not on the other particle, for a time interval Delta t . What is the chargne in the total angular momentum of the two particles ?

Two particle are initially moving with angular momentum vec(L)_(1) and vec(L)_(2) in a region of space with no external torque. A constant external torque vec( tau) then acts on one particle, but not on the other particle, for a time interval Delta t . What is the change in the total angular momentum of the two particles ?

A toruque tau produces an angular acceleration in a body rotating about an axis of rotation. The moment of inertia of the body is increased by 50% by redistributing the masses, about the axis of rotation. To maintain the same angular acceleration, the torque is changed to tau' . What is the relation between tau and tau' ?

If no external torque acts on a body, will its angular velocity be constant?

(A) : When there is no external torque moment of inertia of a rotating body changes, its angular momentum remain conserved, but its kinetic energy changes. (R ) : Angular momentum does not depend upon moment of inertia of the body.

When no external torque acts on a system, its angular momentum remains constant. Is the statement true ? Should kinetic energ of rotation of the system remain constant ? If yes, why , and if no, why not?