Physics (AS & A Level) · May / June 2017 · Paper 12 · Question 10

A metal cylinder is suspended vertically in equilibrium by a cord. The diagram shows the cylinder in four different positions P, Q, R and S. Which statement explains the variation of the tension T in the cord?

1. AAt P and at Q, the tension T in the cord is the same because the difference in pressure between the top and bottom of the cylinder is the same.
2. BAt Q, the tension T in the cord is less than at P because, at smaller depth, liquid pressure is smaller.
3. CAt R, the tension T in the cord is less than at P because atmospheric pressure is less than water pressure.
4. DAt S, the tension T in the cord is greater than at P because atmospheric pressure at S exerts no force on the top or bottom of the cylinder.

As printed in the paper