The motion which repeats itself at regular intervals is called periodic motion. motion which does not repeat at regular intervals is called non periodic motion .

Non-periodic Motion:
Non-periodic motion refers to the motion of an object that does not repeat itself over a specific time interval. In other words, it does not follow a regular pattern and does not return to its initial position after a certain period of time.

Examples of Non-periodic Motion:
1. Motion of a car on a road with varying speed and direction.
2. Motion of a bouncing ball, where each bounce is slightly different from the previous one.
3. Motion of a pendulum when it is pushed with varying force.

Characteristics of Non-periodic Motion:
1. It does not follow a specific pattern or cycle.
2. The motion is irregular and unpredictable.
3. The object does not return to its initial position.
4. The time taken for each cycle may vary.

Periodic Motion:
Periodic motion refers to the motion of an object that repeats itself over a specific time interval. It follows a regular and predictable pattern, returning to its initial position after completing each cycle.

Examples of Periodic Motion:
1. Motion of a swinging pendulum, where it oscillates back and forth in a regular manner.
2. Motion of a child on a swing, where the child moves to and fro repeatedly.
3. Motion of a vibrating guitar string, where it produces a regular pattern of sound waves.

Characteristics of Periodic Motion:
1. It follows a specific pattern or cycle.
2. The motion is regular and predictable.
3. The object returns to its initial position after completing each cycle.
4. The time taken for each cycle remains constant.

Key Differences:
1. Non-periodic motion does not follow a specific pattern, while periodic motion follows a regular pattern.
2. Non-periodic motion does not repeat itself over a specific time interval, while periodic motion repeats itself after completing each cycle.
3. Non-periodic motion is irregular and unpredictable, while periodic motion is regular and predictable.
4. Non-periodic motion does not return to its initial position, while periodic motion returns to its initial position after completing each cycle.
5. The time taken for each cycle in non-periodic motion may vary, while the time taken for each cycle in periodic motion remains constant.