Study the image below and answer the question.

The following is the graph between potential energy between nucleons versus the separation between them. It is seen that the potential energy is a minimum at a distance r_o of about 0.8 fm.

Two nucleons are placed at a distance of 20 fm. What can you say about them?

The force between them is zero

• After a distance of few fermimeters, the forces between the nucleons falls to zero.
• the potential will then onwards remain constant.