The coefficient of restitution for a particle colliding with the body is given as e. If vf is the final velocity and vᵢ is the initial velocity, the velocity of the particle after the collision is given by:
a) vf = e . vᵢ
b) vf = 1/e . vᵢ
c) vf = e² . vᵢ
d) vf = √e . vᵢ