Question

Multiple threads are used to secure

(a) low efficiency

(b) high efficiency

(c) high load lifting capacity

(d) high mechanical advantage

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

My question comes from Efficiency of Self Locking Screws in division Friction of Machine Kinematics

Answer 1

Correct choice is (b) high efficiency

The best I can explain: The power screws with multiple threads such as double, triple etc. are employed when it is desired to secure a large lead with fine threads or high efficiency. Such type of threads are usually found in high speed actuators.