Two persons are pulling a heavy block with the help of horizontal inextensible strings. At the instant shown, the velocities of the two persons are `v_(1)` and `v_(2)` directed along the respective strings with the strings making an angle of `60^(@)` between them.
(a) Find the speed of the block at the instant shown.
(b) For what ratio of `v_(1)` and `v_(2)` the instantaneous velocity of the block will be along the direction of `v_(1)`.
