A disc of the moment of inertia `'l_(1)'` is rotating in horizontal plane about an axis passing through a centre and perpendicular to its plane with constant angular speed `'omega_(1)'` . Another disc of moment of inertia `'I_(2)'`. having zero angular speed is placed discs are rotating disc. Now, both the discs are rotating with constant angular speed `'omega_(2)'`. The energy lost by the initial rotating disc is

Options

A. `1/2 [(I_(1)+I_(2))/(I_(1)I_(2))] omega_(1)^(2)`
B. `1/2 [(I_(1)I_(2))/(I_(1)-I_(2))] omega_(1)^(2)`
C. `1/2[(I_(1)-I_(2))/(I_(1)I_(2))]omega_(1)^(2)`
D. `1/2[(I_(1)I_(2))/(I_(1)+I_(2))]omega_(1)^(2)`

Answer

D