Physics (AS & A Level) · Feb / March 2022 · Paper 12 · Question 12

A cube WXZY has sides of length 2.0 cm and mass 24.0 g. The cube rests on a metre rule of negligible mass. The geometrical centre of the cube is vertically above the 70.0 cm mark on the scale of the rule. The cube has a non-uniform density so that its centre of gravity is not at its geometrical centre. The centre of gravity of the cube is in the plane of the diagram. The rule rests on a pivot at the 50.0 cm mark. A mass of 23.4 g is placed vertically above the 30.0 cm mark. The rule is horizontal and in equilibrium. What can be determined about the position of the centre of gravity of the cube?

1. AIt must be somewhere along a horizontal line that is 0.5 cm from line WX.
2. BIt must be somewhere along a horizontal line that is 0.5 cm from line YZ.
3. CIt must be somewhere along a vertical line that is 0.5 cm from line WY.
4. DIt must be somewhere along a vertical line that is 0.5 cm from line XZ.

As printed in the paper