BRAINCAKEFluids
Revision notes for Fluids in Edexcel Physics (8PH0). Every lesson in BrainCake comes with R.E.C.I.P.E. recall steps, a quick check and spaced reviews.
- FluidsA fluid is defined as any substance that can flow.
- Densitydensity ρ = mass (kg) volume (m3) The units of density are kg m-3 Density is mass per unit volume.
- UpthrustUpthrust is the upwards force felt by a submerged object caused by fluid pressure.
- Floating and SinkingAn object will sink if the upthrust is less than the weight.
- HydrometerA hydrometer is an instrument used to measure density.
- Laminar FlowLaminar flow or streamline flow occurs at relatively low speeds.
- Turbulent FlowWith turbulent flow the fluid velocity at a particular place changes over time.
- StreamliningThe lines of laminar flow are called streamlines.
- ViscosityThe frictional force in fluids caused by movement through the fluid is due to viscosity.
- Investigating Flow RatesThe rate of flow of a fluid through a pipe is inversely proportional to the viscosity of the fluid.
- Investigating Viscosity Changes with TemperatureThe viscosity can be calculated by allowing small spherical objects of known weight to fall through a fluid until they reach terminal velocity.
- Viscous DragViscous drag is the frictional force between a solid and a fluid.
- Stokes' LawStokes' law is the equation for the viscous drag F on a small sphere at low speeds.
- Terminal VelocityFor a small sphere of radius r Volume V = (4/3)πr3 density ρs falling through a fluid of density ρw and viscosity ηw weight of sphere = mg = ρsV g…
- Investigating Terminal VelocityDrop steel ball in viscous fluid and measure terminal velocity by timing how long the ball takes to move a fixed distance and recording the velocity…
On the specification
- Topic 4: Materials