Two forces F1=5 N and F2=8 N acting at points A and B on a rod pivoted at a point O, such that OA = 2 m and OB = 4 m. Calculate the net torque of the two forces about O.
22 N m clockwise
Torque = Force × perpendicular distance between axis of rotation and line of action of force
Torque due to F1 = F1×OA
= 5 N×2 m=10 N m (anticlockwise)
Torque due to F2=F2×OB
= 8 N×4 m=32 N m (clockwise)
∴ Net Torque = 32 Nm−10 N m
= 22 N m (clockwise)