What will be the distance of closest approach of a 5 MeV `alpha`-particle as it approaches a gold nucleus ? (Given atomic no of gold =79)

Explanation

To find the distance of closest approach of a 5 MeV alpha particle as it approaches a gold nucleus, we can follow these steps:

### Step 1: Understand the Problem
The problem involves calculating the distance of closest approach between an alpha particle and a gold nucleus using the concepts of kinetic energy and electrostatic potential energy.

### Step 2: Identify Given Values
- Kinetic Energy (KE) of the alpha particle = 5 MeV
- Atomic number of gold (Z) = 79
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