A particle of mass M is placed at the centre of a uniform spherical shell of equal mass and radius a. Find the gravitational potential at a point P at a distance `a/2` from the centre.

Explanation

To find the gravitational potential at a point P located at a distance \( \frac{a}{2} \) from the center of a uniform spherical shell of mass \( M \) and radius \( a \), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Setup**:
- We have a particle of mass \( M \) at the center of a spherical shell of the same mass \( M \) and radius \( a \).
- We need to calculate the gravitational potential at a point \( P \) which is located at a distance \( \frac{a}{2} \) from the center of the shell.

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