Question

The diagram shows a wheel of diameter 4 m, and pivoted at O. Calculate the moment of force about point (a) O, (b) Q, when a force F = 4 N acts at point P or Q.

Answer 1

Diameter of wheel = 4 m

∴ Radius of wheel = 2 m

(a) Moment of force about point O = F × ⊥ distance

= 4 N × 2 m

= 8 Nm in ACWD

(b) Moment of force about point Q = F × ⊥ distance between O and Q

= 4 N × 2 m

= 8 Nm in CWD