A thin uniform circular disc of mass M and radius R is rotating in a horizontal plane about an axis passing through its centre and perpendicular to the plane with angular velocity `omega`. Another disc of same mass but half the radius is gently placed over it coaxially. The angular speed ofthe composite disc will be:

Options

A. `5 omega//4`
B. `4 omega//5`
C. `2 omega//5`
D. `5omega//2`

Answer

B