Question

Under adiabatic conditions, a moist air parcel cools slowly and rises to greater height in atmosphere compared to a dry air parcel. The reason is that compared to dry air parcel, latent heat of condensation released within the moist air parcel reduces rate of cooling of the moist air parcel moving up under adiabatic conditions. Which of the following is most appropriate?

• A. Both (A) and (R) are correct and (R) is the correct explanation of (A)
• B. Both (A) and (R) are correct but (R) is not the correct explanation of (A)
• C. (A) is correct but (R) is not correct
• D. (A) is not correct but (R) is correct

Hint:

Latent heat release in moist air reduces cooling rate, allowing it to rise higher.

Answer 1

The Correct Option is A

Step 1: Concept
Adiabatic Lapse Rate and Latent Heat.

Step 2: Meaning
The adiabatic lapse rate describes how temperature changes in an air parcel as it moves vertically under adiabatic conditions, where no heat is exchanged with the surroundings. For moist air, latent heat release during condensation affects this process.

Step 3: Analysis
Under adiabatic conditions, a moist air parcel cools more slowly than a dry air parcel when rising because of the latent heat released during condensation. This reduces the rate of cooling for the moist air parcel. Statement (A) correctly identifies that a moist air parcel rises higher under these conditions. Statement (R) correctly explains why: the latent heat reduces the cooling rate.

Step 4: Conclusion
Both (A) and (R) are correct and (R) accurately explains (A). Final Answer: (A)