A person living in shimla observd that cooking without using pressure cooker takes more time. The reason for this observation is that at high altitude

Options

A. pressure increase
B. temperature decreases
C. pressure decreases
D. temperature increases.

Explanation

### Step-by-Step Solution

1. **Understanding the Context**: The question states that a person living in Shimla finds that cooking without a pressure cooker takes more time. This observation is related to the effects of altitude on boiling point and atmospheric pressure.

2. **Comparing Altitude and Sea Level**: At high altitudes, such as Shimla, the atmospheric pressure is lower compared to sea level locations like Goa. This difference in pressure affects the boiling point of water.

3. **Boiling Point and Atmospheric Pressure**: The boiling point of a liquid is the temperature at which its vapor pressure equals the external atmospheric pressure. At lower atmospheric pressure (as in high altitudes), the boiling point of water decreases. This means that water will boil at a temperature lower than 100°C.

4. **Cooking Without a Pressure Cooker**: When cooking without a pressure cooker at high altitudes, the water boils at a lower temperature. Since many cooking processes require water to reach a higher temperature to cook food properly, the lower boiling point results in longer cooking times.

5. **Using a Pressure Cooker**: A pressure cooker increases the internal pressure, which raises the boiling point of water. This allows food to cook at a higher temperature, thereby reducing cooking time.

6. **Conclusion**: Therefore, the reason for the observation that cooking without a pressure cooker takes more time in Shimla is that the boiling point of water is lower due to decreased atmospheric pressure at high altitudes.

### Final Answer
The reason for the observation is that pressure decreases at high altitude, leading to a lower boiling point of water, which increases cooking time.

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