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A particle of mass m travels with speed v and undergoes an inelastic collision with an identical particle initially at rest. After the collision, the first particle moves at speed v/√(3) in a direction at right angles to its original path. What is the speed of the second particle after the collision?

1. √(3)v
2. v
3. v/√(3)
4. 2v/√(3)

Correct answer: 2v/√(3)

Solution

In an inelastic collision, momentum is conserved. The initial momentum of the system is entirely from the first particle, and after the collision, the momentum must be distributed between both particles. By applying conservation of momentum in both the x and y directions, we find that the second particle must move with a speed of 2v/√3 to balance the momentum equations.

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