Question

The second condition of equilibrium of a body is ___

(a) Sum of all force on a body should be zero

(b) Sum of all moments on a body should be zero

(c) Sum of the initial and final force should be zero

(d) Relative difference of forces should be zero

I have been asked this question in unit test.

This is a very interesting question from Laws of Motion in chapter Laws of Motion of Physics – Class 11

Answer 1

Correct answer is (b) Sum of all moments on a body should be zero

To elaborate: The second condition for a body to exist in equilibrium is that the sum of all moments on the body must be zero. Which means that the resultant moment on a body should be zero.