Draw a plot of the binding energy per nucleon as a function of mass number for a large number of nuclei , `2 le A le 240` . How do you explain the constancy of binding energy per nucleon in the range `30 lt A lt 170` using the property that nuclear force is short-ranged ?

Explanation

The plot of the binding energy per nucleon versus the mass number A for a large number of nuclei , `2 le A le 240` is shown in Fig.

The constancy of the binding energy in the range `30 lt A lt 170` is a consequence of the fact that the nuclear force is short-ranged . It will be under the influence of only some of its neighbours , which come within the range of the nuclear force .