Question

A ball with a mass of `3 kg` moving at `1 m/s` hits a still ball with a mass of `7 kg`. If the first ball stops moving, how fast is the second ball moving?

Answer 1

By coservation of momentum `m_1v_1=m_2v_2` here`m_1=3kg,v_1=1ms^-1andm_2=7kg,v_2=?` applying above formula`v_2=3/7ms^-1`