When is the motion of an object categorised as oscillatory motion?

Explanation

### Step-by-Step Solution:

1. **Understanding Periodic Motion**:
- Periodic motion is defined as the motion of an object that repeats itself after a fixed time interval.
- Examples include circular motion, the motion of a simple pendulum, and the motion of a clock hand.

2. **Defining Oscillatory Motion**:
- Oscillatory motion is a specific type of periodic motion characterized by a to-and-fro movement around a central position or equilibrium point.
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