Question

The body is sometimes acted by two or three force members and we need to find the radius of gyration for the same. The difference between the two and the three force members is:

(a) The former is collinear and the latter is parallel

(b) The former is parallel and the latter is perpendicular

(c) The former is perpendicular and the latter is collinear

(d) The former is acting on two points in the body while the latter is on three points

I had been asked this question by my college professor while I was bunking the class.

Question is from Radius of Gyration of an Area topic in portion Moments of Inertia of Engineering Mechanics

Answer 1

Correct option is (d) The former is acting on two points in the body while the latter is on three points

To explain I would say: The definition of the two force member only defines that the forces are being acted on the two points on the body. So does is the definition of the three forces members. The points of action of the three forces are three.