N Impulse on Particle A: Speed of A

[sonu19]

Two particles A & B of masses 3 kg and 4kgr connected by a string and lie at rest on a smooth horizontal table with string taut. B is struck wid a blow directly away from A so that there is an impulse of 8Ns transmited along the string. Find speedd with which A begins to move.
ans is 3/8

 

[jdstokes]

Got any working to show us?