A 1 MeV proton is sent against a gold leaf (Z = 79). Calculate the distance of closest approach for head on collision.

Question

$\begin{array}{1 1}(a)\;1.137\times10^{-13}m\\(b)\;1.137\times10^{-23}m\\(c)\;2.137\times10^{-13}m\\(d)\;1.137\times10^3m\end{array}$