(b) Loss in kinetic energy $= \frac{1}{2}\frac{m_{1}m_{2}\left( u_{1} - u_{2} \right)^{2}}{\left( m_{1} + m_{2} \right)}$ $= \frac{1}{2}\ \frac{m.m\left( u_{1} - u_{2} \right)^{2}}{(m + m\ )}$ $= \frac{m}{4}\left( u_{1} - u_{2} \right)^{2}$
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.