Particle A of mass m1 moving with velocity ( √ 3 ^ i + ^ j ) ms^-1 collides with another particle B of mass m2 which is at rest initially. Let → V1 and V2 be the velocities of particles A and B after collision respectively. If m1 = 2m2 and after collision V1 = ( ^ i + √ 3 ^ j^) ms-1 the angle between V1 and V2 is