two cylindrical hollow drums of radii R and 2 R, and of a common height h , are rotating with angular velocities `omega` (anti- clockwie ) and `omega` (clockwise ) , respectively , their axes , fixed are parallel and in a horizontal plane separted by by 3R + `delta` , they are now brought in contact `(delta to0)`
(A) show frictional forces just after contact .
(B) identify forces and torque external to the system just contact ,
(c) what would be the ratio of final of final angular velocities when friction ceases ?

Explanation

(1)
(ii) F' = F=F('') where F and F'' and external forces through support, External torque `=F xx 3 R`, anti-clockwise,
(ii) Let `omega_(1)` and `omega_(2)` be final angular velocities (anti-clockwise and clockwise respectively),
Finally there will be no friction, Hence, `Romega_(1) = 2Romega_(2) rArr omega_(1)/omega_(2)=2`