A vertical tube is open to the atmosphere at its upper end and contains water. A horizontal piston is 6.0 m below the water surface. The piston has an area of 0.018 m2, and the air beneath it exerts a pressure of 125000 Pa.
The density of water is 1000 kg/m3. Atmospheric pressure is 100000 Pa and the gravitational field strength is 10 N/kg.
Calculate the resultant force exerted on the piston by the water and the air.
132 exam-style questions on Edexcel GCSE Physics 15.2 Pressure in fluids, covering 15.2.1 Atmospheric pressure and height, 15.2.2 Pressure in fluids, 15.2.3 Pressure, force and area, 15.2.4 Pressure and depth, 15.2.5 Pressure in liquids: depth and density, 15.2.6 Upthrust, and 15.2.7 Floating and sinking. Each one has a worked solution and a mark scheme showing where the marks go.