Why the centre of gravity coincides with the centre of mass only if the size of the body is small ?

Explanation

To understand why the center of gravity (COG) coincides with the center of mass (COM) only if the size of the body is small, we can break down the explanation into several steps:

### Step-by-Step Solution

1. **Definition of Center of Mass (COM)**:
- The center of mass of a body is the point where the mass of the body can be considered to be concentrated. It is determined by the distribution of mass within the body.

2. **Definition of Center of Gravity (COG)**:
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