We set up a gentle ramp and measured the time it took the marble to roll between the lines in water and then in baby oil.

The time for the marble to roll down in the bay oil was greater than the time to roll down the same distance in water. From the data, we see that baby oil has a higher viscosity than water.

Try these ideas

Here are some additional variations to try. Repeat the experiment using:

1. a marble of a different size.
2. two other different liquids.
3. a taller bottle or a different rolling distance.

Or, try Another Viscosity of Liquids Experiment.

Have you wondered what would happen for the same liquid at different temperatures? Good thinking! That's what the Temperature and Viscosity activity is all about. Give it a try!