The moment of a force of 20 N about a fixed point O is 10 N m. Calculate the distance of the point O from the line of action of the force.

Moment of force = F × r

Substituting values in the above formula we get,

10 = 20 × r

⇒ r = 10\over 20 = 0.5 m

Hence, distance of the point O from the line of action of the force is 0.5 m.