A circular disc of mass `M_(1)` and radius `R`, initially moving, With a constant angular speed `omega` is gently placed coaxially on a stationary circular disc of mass ` M_(2)` and radius `R`, as shown in Fig. There is a frictional force between the two discs.
If disc `M_(2)` is placed on a smooth surface, then 'determine' the final angular speed of each disc.
b. Determine the work done by friction.
c. Determine the frictional loss in kinetic energy. i.e. `/_\K//K_(i)`

Options

A. `(m_(1))/(m_(2))`
B. `(m_(2))/(m_(1)+m_(2))`
C. `(m_(2))/(m_(1))`
D. `(m_(1))/(m_(1) + m_(2))`

Answer

B