Question

Which of the following is not the method to prevent rotation of a bolt while screwing a nut on or off it?

(a) By keeping a square neck

(b) By providing a snug

(c) By keeping a lock nut

(d) By inserting a pin in shank

I had been asked this question by my school teacher while I was bunking the class.

The doubt is from Bolts topic in chapter Screw Threads & Screwed Fastening of Engineering Drawing

Answer 1

The correct choice is (c) By keeping a lock nut

To explain: The connected parts might get loose, and lead to serious breakdown a lock nut in some way so as to prevent it from getting loose but not to prevent rotation of a bolt while screwing a nut on or off.