#### A thin circular ring of mass M and radius R is rotating about its axis with a constant angular velocity ω . Two objects, each of mass m are attached gently to the opposite ends of the diameter of the ring. The wheel now rotates with an angular velocity. Option 1) ω M/(M + m) Option 2) {(M – 2m)/(M +2m)}ω Option 3) {M/(M + 2m)}ω Option 4) {(M + 2m)/M} ω

As we discussed in concept

Law of conservation of angular moment -

- wherein

If net torque is zero

i.e.

angular momentum is conserved only when external torque is zero .

Option 1)

ω M/(M + m)

This is incorrect option

Option 2)

{(M – 2m)/(M +2m)}ω

This is incorrect option

Option 3)

{M/(M + 2m)}ω

This is correct option

Option 4)

{(M + 2m)/M} ω

This is incorrect option