Define amplitude of `S.H.M.` ?

Answer

### Step-by-Step Solution:

1. **Definition of Amplitude**:
- Amplitude in the context of Simple Harmonic Motion (S.H.M.) is defined as the maximum displacement of the oscillating object from its mean (equilibrium) position.

2. **Understanding Mean Position**:
- The mean position is the central point around which the motion occurs. It is the position where the object would rest if there were no oscillation.

3. **Maximum Displacement**:
- The amplitude is the distance from the mean position to the farthest point the object reaches during its oscillation. This can be in both positive and negative directions.

4. **Notation**:
- Amplitude is commonly denoted by the letter "A".

5. **Visual Representation**:
- If we visualize the motion on a line, the mean position is at the center. The maximum displacement to the right is called the positive extreme position, and the maximum displacement to the left is called the negative extreme position. Both of these extremes are at the same distance from the mean position, which is the amplitude.

6. **Conclusion**:
- Therefore, the amplitude can be understood as the distance from the mean position to either the positive or negative extreme position, and it is a crucial parameter in describing the characteristics of simple harmonic motion.