Which of the following is correct?
(a) The application of the conditions of the equilibrium of the body is valid only if the forces are collinear
(b) The application of the conditions of the equilibrium of the body is valid only if the forces are parallel
(c) The application of the conditions of the equilibrium of the body is valid only if the forces are perpendicular
(d) The application of the conditions of the equilibrium of the body is valid throughout
The question was posed to me during a job interview.
Question is taken from Conditions for a Rigid-Body Equilibrium topic in section Equilibrium of a Rigid Body of Engineering Mechanics