Define mechanical energy and law of conservation of mechanical energy. Prove conversion of gravitational potential energy in to kinetic energy by the help of law of conservation of mechanical energy. Also draw graph between energy and height.

Explanation

### Step-by-Step Solution:

1. **Definition of Mechanical Energy**:
Mechanical energy is defined as the sum of kinetic energy (KE) and potential energy (PE) in a system. Mathematically, it can be expressed as:
\[ \text{Mechanical Energy} (E) = \text{Kinetic Energy} (KE) + \text{Potential Energy} (PE) \]

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