What happens to the kinetic energy of the particle at the distance of closest approach?

Explanation

To solve the question "What happens to the kinetic energy of the particle at the distance of closest approach?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Concept of Distance of Closest Approach**:
- The distance of closest approach refers to the minimum distance between the alpha particle and the nucleus of an atom (e.g., a gold atom) during a scattering experiment. At this point, the alpha particle is closest to the nucleus before it is repelled.

**Hint**: Remember that this distance is significant in understanding the interaction between charged particles.
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