Describe how you could determine the centre of gravity of an irregularly shaped piece of card using the edge of the ruler
instead of the plumb-line method (4marks)

Explain why the centre of gravity for a table-tennis ball is in the empty space inside the ball, rather than in the plastic of the
ball itself. (2marks)

Suggest how you can locate the centre of mass of an object
in space where there is no detectable gravitational field.
4 marks