Question

All the forces need to be collinear in the three force system. Then only they will for the equilibrium state.

(a) The first part of the statement is false and other part is true

(b) The first part of the statement is false and other part is false too

(c) The first part of the statement is true and other part is false

(d) The first part of the statement is true and other part is true too

I have been asked this question by my college director while I was bunking the class.

Question is taken from Two and Three Force Members in chapter Equilibrium of a Rigid Body of Engineering Mechanics

Answer 1

The correct choice is (d) The first part of the statement is true and other part is true too

For explanation: The forces need to be collinear. If they are not so then the equilibrium is not possible. If they are parallel too, then it is assumed that they are meeting in the infinity. And hence the equilibrium is established between the forces. Thus the forces must be collinear.