2015 Cambridge International AS & A level November Physics Paper 11 Q. No. 19 (9702/11/O/N/15) by Sajit Chandra Shakya from Nepal Chapter - DENSITY and PRESSURE A U-tube closed at one end contains mercury. Air at a pressure of 5.0 × 104Pa is trapped at the closed end. The other end is open to the atmosphere and is fitted with a piston of mass 5.0kg and cross-sectional area 5.0 × 10–4m2. The density of mercury is 13600kgm–3 and atmospheric pressure is 1.01 × 105Pa. What is the height h of the mercury column?