Consider a gold nucleus to be a sphere of redius 6.9 fermi in whichprotons and neutrons are distributed. Find the force of repulsion between two protons situated at largest separaton. Why do thes protons not fly apart under this repulsion

Explanation

To find the force of repulsion between two protons situated at the largest separation in a gold nucleus, we will follow these steps:

### Step 1: Determine the radius and largest separation
The radius of the gold nucleus is given as \( r = 6.9 \) Fermi. The largest separation between two protons will be equal to the diameter of the nucleus.

\[ \text{Largest separation} = 2r = 2 \times 6.9 \text{ Fermi} = 13.8 \text{ Fermi} \]
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