Question

The 'ratchet and pawl' mechanism in a jack hammer drill

• A. Prevents reverse rotation of rifle bar
• B. Forces down the piston
• C. Engages rifle bar with rifle nut
• D. Provides a twisting force to the drill steel

Hint:

A ratchet and pawl mechanism always \[ \boxed{ \text{Allows one-way rotation and prevents reverse motion.} } \]

Answer 1

The Correct Option is A

Step 1: Recall the function of a ratchet and pawl mechanism. A ratchet and pawl mechanism permits motion in one direction while preventing motion in the opposite direction.

Step 2: Apply it to a jack hammer drill. In a jack hammer drill, the mechanism prevents the reverse rotation of the rifle bar while allowing forward rotation. Hence, \[ \boxed{\text{Prevents reverse rotation of rifle bar}.} \] Therefore, \[ \boxed{(A)} \] is the correct answer.