Question

two horizontal discs rotate freely about a vertical axis passing through their centers .the moments of inertia of discs relative to this axis are equal to i1 and i2 .and the angular velocities to w1 and w2.when the upper disc fell on the lower one both discs began rotating, after some time as a single whole(due to friction).find
a)the steady state angular rotational velocity of the discs.
b) the work performed by frictional forces in this process

Answer 1

@dan613 @dan815 @Compassionate

Answer 2

@_Darkmeadow

Answer 3

@Mimi_x3