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Assertion : In desert area, days get hot...

Assertion : In desert area, days get hot fastly and the nights get cold fastly .
Reason : The specific heat capacity for air and land is less than that of water.

A

If both assertion and reason are true and reason is the correct explanation of assertion.

B

If both assertion and reason are true but reason is the currect explanation of assertion.

C

If assertion is true but reason is false.

D

If both assertion and reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the assertion and reason question, we need to analyze both statements and determine their validity and relationship. ### Step-by-Step Solution: 1. **Understanding the Assertion**: - The assertion states that in desert areas, days get hot quickly and nights get cold quickly. This is a characteristic of deserts due to their geographical and climatic conditions. 2. **Understanding the Reason**: - The reason provided is that the specific heat capacity for air and land is less than that of water. Specific heat capacity is the amount of heat required to raise the temperature of a unit mass of a substance by one degree Celsius. 3. **Specific Heat Capacity Values**: - The specific heat capacity of water is approximately 4200 J/kg°C, which is quite high. This means water can absorb a lot of heat without a significant change in temperature. - In contrast, land (soil) and air have much lower specific heat capacities. This means they can heat up and cool down much more quickly than water. 4. **Linking Assertion and Reason**: - Since land heats up quickly during the day and cools down quickly at night, this is due to its lower specific heat capacity compared to water. Water retains heat longer, while land does not. - Therefore, the reason correctly explains why the assertion is true. 5. **Conclusion**: - Both the assertion and the reason are true, and the reason provides a valid explanation for the assertion. ### Final Answer: Both the assertion and the reason are true, and the reason correctly explains the assertion. ---
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