Question

What is Varigon’s Theorem? (M = Moment, F= Force vector, R= Radius vector)

(a) M = R x F (F = F1 + F2 + F3 + … vectorially adding all the forces)

(b) |A||B|sinØ

(c) AxB)xS ≠ Px(QxS)

(d) Px(Q+S) = (PxQ) + (PxS)

This question was posed to me during an internship interview.

Asked question is from Dot Product and Cross Product in section Force Vectors of Engineering Mechanics

Answer 1

Correct choice is (a) M = R x F (F = F1 + F2 + F3 + … vectorially adding all the forces)

Explanation: For many vectors acting on the body, Varigon’s Theorem is defined as M = R x F (F = F1 + F2 + F3 + … vectorially adding all the forces). This is just the giving the cross product of individual force and radius vectors and thus the sum is the total moment produced.