Tornado can be called a periodic change.

Answer

To determine whether the statement "Tornado can be called a periodic change" is true or false, we need to analyze the definitions and characteristics of periodic changes and tornadoes.

### Step-by-Step Solution:

1. **Understand the Definition of Periodic Change**:
- A periodic change is defined as a change that occurs at fixed intervals of time. These changes happen regularly and can be predicted based on a specific time frame.

2. **Examples of Periodic Changes**:
- Examples include the rotation of the Earth, the revolution of the Earth around the Sun, and the occurrence of day and night. All these events happen in a predictable and regular manner.

3. **Analyze Tornadoes**:
- Tornadoes are natural disasters characterized by violent winds and can occur suddenly. Unlike periodic changes, tornadoes do not have a fixed schedule or predictable intervals.

4. **Nature of Tornado Occurrence**:
- Tornadoes can happen at any time and in various locations, making them unpredictable. There is no regularity or fixed interval associated with their occurrence.

5. **Conclusion**:
- Since tornadoes do not occur at fixed intervals and cannot be predicted, they do not fit the definition of periodic changes. Therefore, the statement "Tornado can be called a periodic change" is **false**.

### Final Answer:
The statement is **false**. Tornadoes are non-periodic changes as they do not occur at fixed intervals of time.

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