Q. If in Rutherford’s experiment, the number of particles scattered at $90{^\circ}$ angle are 28 per $\min$, then number of scattered particles at an angle $60{^\circ}$ and $120{^\circ}$ will be
A) $112/min,12.5/min$
B) $100/min,200/min$
C) $50/min,125.5/min$
D) $117/min,25/min$
Explanation
(a) $N \propto \left\lbrack \frac{1}{\sin^{4}{\theta/2}} \right\rbrack \Rightarrow N_{1} = 7 \times \frac{1}{\left( \sin{30{^\circ}} \right)^{4}} = 112$
and $N_{2} = 7 \times \frac{1}{\left( \sin{60{^\circ}} \right)^{4}} = 12.5$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.