A sealed plastic marker is held fully under water. It displaces 0.020 m3 of water. The marker has a weight of 120 N.
| Quantity | Value |
|---|---|
| Density of water, ρ\rhoρ | 1000 kg/m3 |
| Gravitational field strength, ggg | 10 N/kg |
The upthrust is given by
U=ρVgU=\rho VgU=ρVg
The marker is released and rises until it is floating at rest.
Use the equation above to calculate the upthrust acting on the marker while it is fully under water.
Calculate the volume of water displaced by the marker when it is floating at rest.
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.