PHYSICAClass 11 Physics simulations · Mechanical Properties of Fluids
Viscous drag and terminal speed
Release a small sphere in thick liquid and watch drag grow until the forces balance.
What to notice
Weight is downward. Buoyancy and viscous drag act upward, reducing the acceleration as speed rises.
Key relation
vterminal = 2r²(ρs − ρf)g/(9η)
Try this
Double the sphere radius and compare the terminal speed.
What you can change
- Sphere radius: 0.5 to 2 mm
- Dynamic viscosity: 2 to 10 Pa·s
- Sphere density: 2000 to 8000 kg/m³
More in Mechanical Properties of Fluids
- Lift on an aerofoil
- Float or sink?
- Capillary rise and depression
- Flow through a narrowing pipe
- Pressure inside drops and bubbles
- Hydraulic lift (Pascal)
- Pressure at depth in a tank
- Water jet from a tank
- Venturimeter
See all Class 11 Physics simulations or every Physica simulation.