Question

In Rutherford's $\alpha$-particle scattering experiment, what will be correct angle for $\alpha$ scattering for an impact parameter $b=0$?

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

Answer 1

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

Impact parameter is the closest distance the alpha particle would have been to the nucleus had there been no Coulomb repulsion.

Zero impact parameter means that it is directed towards the nucleus and would, thus, simply bounce that due to force of repulsion acting along the line of motion. Thus the scattering angle is ${180}^{\circ }$.