Statement-`1`: When an electric fan is switched on in a closed room, the air of the room is cooled.
Statement-`2`: When fan is switched on, the speed of the air molecules will increase.

Options

A. Statement -`1` is True , Statement -`2` is True , Statement -`2` is correct explanation for Statement - `1`
B. Statement -`1` is True , Statement -`2` is True , Statement -`2` is not correct explanation for Statement - `1`
C. Statement -`1` is True , Statement -`2` is False.
D. Statement -`1` is False , Statement -`2` is True.

Answer

To analyze the statements provided in the question, we will evaluate each statement individually and then determine the relationship between them.

### Step 1: Evaluate Statement 1
**Statement 1**: When an electric fan is switched on in a closed room, the air of the room is cooled.

- When a fan is switched on, it creates air movement. This movement helps in the evaporation of sweat from our skin. As sweat evaporates, it absorbs heat from the body, leading to a cooling sensation.
- However, the fan does not actually lower the temperature of the air in the room; it merely facilitates the cooling effect on our skin. Therefore, while we may feel cooler, the air temperature itself does not decrease significantly.

**Conclusion for Statement 1**: This statement is somewhat misleading. The air does not cool down in temperature, but we feel cooler due to the evaporation of sweat.

### Step 2: Evaluate Statement 2
**Statement 2**: When the fan is switched on, the speed of the air molecules will increase.

- When the fan is turned on, it causes the air to move. This movement increases the kinetic energy of the air molecules, which means their speed increases.
- The fan blades push the air, creating a flow that increases the speed of the air molecules in the vicinity of the fan.

**Conclusion for Statement 2**: This statement is true. The speed of the air molecules does indeed increase when the fan is switched on.

### Step 3: Determine the Relationship Between the Statements
- Both statements are true, but they refer to different phenomena. Statement 1 discusses the cooling effect on humans due to evaporation, while Statement 2 discusses the increase in speed of air molecules due to the fan's operation.

### Final Conclusion
- **Statement 1**: Misleading, as it implies a decrease in air temperature.
- **Statement 2**: True, as it correctly describes the effect of the fan on air molecules.

### Answer
Both statements have elements of truth, but Statement 1 is misleading in its implication about air temperature.

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