Originally Posted by

**jackiemoon** Hi,

Can anybody help with this question please?

Two particles of mass m are joined by a thin rigid rod of negligible mass and length l. They lie on a frictionless plane and a third particle of mass m, travelling with speed V0 hits one of the two particles in the way depicted in the attached figure.

Compute the angular velocity of the rod about its mid point after the collision -

a) if the collision is elastic, so that the third mass recoils and moves straight back;

b) if the collision is completely inelastic, i.e. if the two particles colliding get stuck together.

Thanks