Question

The diagram shows a wheel with a handle. Two forces, F₁ and F₂ of equal magnitudes are acting on the handle as shown in the diagram.

1. Which force produces negative moment?
2. Is the wheel in equilibrium? (Yes or No)
3. Justify your answer stated in (b).

Answer 1

1. The force F₁ produces the negative moment because it tends to rotate the wheel in the clockwise direction, which is taken as negative.
2. No, the wheel is not in equilibrium.
3. For equilibrium, the sum of clockwise moments must equal the sum of anticlockwise moments about the centre O. While F₁ and F₂ have equal magnitudes, their respective perpendicular distances from the centre (moment arms) differ. Hence, the moments generated by them are neither equal nor opposite, resulting in a non-zero net moment, and so the wheel is not in a state of equilibrium.