Question
Consider a head-on collision between two particles of masses m1 and m2. The initial speeds of the particles are u1 and u2 in the same direction. The collision starts at t = 0 and the particles interact for a time interval Δt. During the collision, the speed of the first particle varies as
v(t)=u1+tΔt(v1−u1)
Find the speed of the second particle as a function of time during the collision.