A motion which repeats itself after a fixed interval of time is called periodic motion. True/false.

Answer

To determine whether the statement "A motion which repeats itself after a fixed interval of time is called periodic motion" is true or false, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Motion**:
- Motion refers to the change in position of an object with respect to time.

2. **Defining Periodic Motion**:
- Periodic motion is defined as motion that repeats itself at regular intervals of time.

3. **Analyzing the Statement**:
- The statement claims that a motion which repeats itself after a fixed interval of time is termed periodic motion.

4. **Evaluating the Definition**:
- Since periodic motion is characterized by its repetitive nature over a consistent time frame, the statement aligns with the definition of periodic motion.

5. **Conclusion**:
- Therefore, the statement is true. A motion that repeats itself after a fixed interval of time is indeed called periodic motion.

### Final Answer:
**True**