Q. A radioactive nucleus of mass $M$ emits a photon of frequency $v$ and the nucleus recoils. The recoil energy will be
A) $hv$
B) $Mc^{2} - hv$
C) $\frac{h^{2}v^{2}}{2Mc^{2}}$
D) Zero
Explanation
(c) $E = \frac{(momentum)^{2}}{2M} = \frac{\left( \frac{hv}{c} \right)^{2}}{2M}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.