Question

Given below are two statements, one is labelled as Assertion (A) and other one labelled as Reason (R).

Assertion (A): In a rubber roll sheller, paddy is sheared and compressed between two rollers so that its husk is stripped off.

Reason (R): Rollers in a rubber roll sheller rotate in same direction at different speed to increase contact of one roll longer than the other roll.

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:

Picture two rolls gripping a grain between them. For the grain to be pulled through, which way must the rolls actually spin relative to each other?

Answer 1

The Correct Option is C

Step 1: Recall how a rubber roll sheller dehusks paddy. Paddy grains pass through the gap between two rubber covered rolls that press against each other, and the husk is peeled off by a combination of shear and compression as the grain squeezes through.

Step 2: Assertion (A) states this exact mechanism, shearing and compressing paddy between two rollers to strip the husk. This matches how the machine actually works, so (A) is true.

Step 3: Now check Reason (R). It claims the two rolls rotate in the same direction at different speeds. In an actual rubber roll sheller, the two rolls rotate towards each other, meaning in opposite directions, so that the grain gets pulled and squeezed into the gap between them. They do run at different peripheral speeds, typically with a speed ratio of about 1.5 to 1, and that speed difference is what creates the shearing action that removes the husk. But the claim of same direction rotation is incorrect.

Step 4: Since (A) correctly describes the shelling action but (R) wrongly states the direction of rotation, (A) is true and (R) is false.

Why the other options fail: Options 1 and 2 both need (R) to be true, which it is not because the rolls turn opposite to each other, not in the same direction. Option 4 needs (A) to be false, but (A) correctly describes the shelling mechanism.