Question

An α-particle of energy 5MeV is scattered through 180° by a fixed uranium nucleus. The distance of the closest approach is of the order of

(a) 1Å 

(b) 10^–10cm

(c) 10^–12cm 

(d) 10^–15cm.

Answer 1

(c) : Kinetic energy is converted into potential energy at closest approach
Therefore, K.E. = P.E.