Practical - Terminal Velocity

These experiments use a thick viscous liquid to investigate balanced forces on a moving object.


1. Investigating Terminal Velocity

There are a lot of ways to investigate the terminal velocity of an object moving through a fluid. You can drop paper cupcake cases, or in this example a ball bearing through bubble bath. The exact set up varies with the equipment at your school, but in this video I explain how you can use video to record the data which is then analysed.


2. Viscosity of a Liquid

This is an extension task that allows you to calculate the viscosity of the liquid that an object is moving through. The equation looks daunting and relies on Stokes' Law, however, once you have measured all the terms you simply input the data to find a value for viscosity.