Moments and equilibriumEdexcel International A Level Physics: Mind map

Exam questions on Moments and equilibrium

1. A mechanic uses a spanner with a handle 0.25 m long to tighten a nut. The force is applied at the end of the handle, and the axis of rotation is the centre of the nut.
   Explain why a longer spanner makes it easier to turn the nut.2 marks
2. A uniform plank of length 4.0 m and weight 200 N rests horizontally on two supports, A at its left end and B at its right end. A child of weight 600 N stands on the plank 1.0 m from A.
   State what is meant by the centre of gravity of an object, and explain why the weight of the plank can be taken to act at a point 2.0 m from A.2 marks
3. A uniform metre rule of weight 1.0 N is pivoted on a knife edge at the 30.0 cm mark. A 2.0 N weight is hung from the 5.0 cm mark and a weight W is hung from the 90.0 cm mark. The rule balances horizontally.
   Calculate the weight W.3 marks