Question

In Rutherford scattering experiment, the correct angle of scattering of $\alpha -$ particles for impact parameter equal to zero is

• A. ${90}^0$
• B. ${120}^0$
• C. ${270}^0$
• D. ${180}^0$

Answer 1

The correct option is D ${180}^0$

For impact parameter $=0.$
This means that the particle undergoes a full reflection (bounce back)
Momentum change $=2$ times initial momentum (with direction reversed)
i.e. $\alpha ={180}^{\circ }$