Question

In rolling, there is the involvement of the vector math. So for rolling which of the following is correct? (For A representing the vector representation of the axis of rotation, r the radius vector and F the force vector)

(a) A.(rxF)

(b) Ax(rxF)

(c) A.(r.F)

(d) Fx(r.F)

I had been asked this question during an interview.

My doubt is from Rolling Resistance in section Friction of Engineering Mechanics

Answer 1

Correct option is (a) A.(rxF)

The explanation is: The correct form of the equation is given by A.(rxF). Where A represents the vector representation of the axis of rotation, r the radius vector and F the force vector. This is usually done for determining the moment of the force about the axis. That is if the body is being rotated by the force about an axis.