Question

A car of mass 2500 kg and moving at 3 m/s, northeast collides with 3800 kg car moving northwest at 2 m/s. Find their velocity, assuming that the collision is perfectly inelastic.

Answer 1

$$Ox: m_1v_1=(m_1+m_2)u\sin\theta,\\ Oy: m_2v_2=(m_1+m_2)u\cos\theta,\\\space\\ \theta=44.6°,\\ u=1.69\text{ m/s}.$$