Question

Assertion (A): Only about 70% to 80% of the circumference of the drum can be effectively used for drying in drum dryer.
Reason (R): Feed and discharge cannot be at the same point for reasons of construction.
In light of the above statements, choose the correct answer from the options given below:

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

Hint:

Drum dryer: 70-80% circumference used.
Feed and discharge points limit effective area.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Drum dryers have specific operational limitations.
The effective drying surface is not the entire drum.

Step 2: Key Formula or Approach:
No specific formula.
Need to understand drum dryer operation.

Step 3: Detailed Explanation:
Assertion A: Only 70-80% of the drum circumference is used - true.
Reason R: Feed and discharge cannot be at the same point due to construction - true.
The reason explains why the full circumference is not used.
Thus, both A and R are true, and R explains A.

Step 4: Final Answer:
Both (A) and (R) are true and (R) is the correct explanation of (A).
Hence, the correct option is (A).