Question
Two particles of mass m1 and m2 in projectile motion have velocities →v1<→v2 respectively at tine t=0. They collide at time t0. Their velocities become →v′1 and →v′2 at time 2t0′ while still moving in air. The value of ∣∣(m1→v′1+m2→v′2)−(m1→v1+m2→v2)∣∣ is