1.A block of mass $m=2\text{ kg}$ compresses a spring of constant $k=400\text{ N/m}$ by $0.1\text{ m}$ on a smooth floor and released. Find speed of block as it leaves spring.
2.Find the minimum initial speed required for a particle attached to a light inextensible string of length $L$ to complete a full vertical circle.
3.A head-on elastic collision occurs between mass $m_1$ moving with speed $v_1$ and stationary mass $m_2$. Find final velocities $v_1'$ and $v_2'$.
