Question

A screw jack is said to be self locking if its efficiency

Answer 1

A screw is a mechanism that converts rotational motion to linear motion, and a torque (rotational force) to a linear force.It is one of the six classical simple machines. The most common form consists of a cylindrical shaft with helical grooves or ridges called threads around the outside.The screw passes through a hole in another object or medium, with threads on the inside of the hole that mesh with the screw's threads.

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