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velocity of mass m2 along the incline will not change let the velocity of mass m2 perpendicular to incline after collision be V

 

hence net velocity V2 after collision of mass M2 will be root(v^2 + (u2sin)^2)

 

let velocity of mass M1 after collision be V1 towards left which is component of Va

 

so along common normal direction of collision i.e perp. to incline

we have

 

V + Va = e (U2cos)--------------------------1

 

conserving momentum along this direction

 

M1Va - M2V = M2U2cos  ------------------2

 

solve 1 &2 to get Va and V

 

hence V1 is Vasin & V2 is  root(v^2 + (u2sin)^2)