Question

For getting the normal force on the supports, we do what?

(a) Make the vertical sum of the forces equal to zero

(b) Make the horizontal sum of the forces equal to zero

(c) Make the moment sum of the forces equal to zero

(d) Make the rotational sum of the forces equal to zero

I got this question during an interview.

My question is based upon Internal Forces Developed in Structural Members in section Internal Forces of Engineering Mechanics

Answer 1

Correct answer is (a) Make the vertical sum of the forces equal to zero

To elaborate: The making of the vertical force sum zero makes the normal force to be determined. This means that the equilibrium equations when applied at the support give us the answer. Hence the determination of the normal force is done easily by equating the vertical force sum equal to zero.