Go Go Gears

On blue and black table top, sits multiple different coloured and sized gears, interlinked and sitting in a green tub.
A blue and black table with a brown and white information panel at the back. On the table top, sits multiple different coloured and sized gears, interlinked and sitting in a green tub.

Different sized gears can be used to magnify force or distance (speed).

How it works

Interlock rows of different sized gears and make an illusoin disc spin.

Things to try or ask around the exhibit

  • What's the difference between the way a small gear spins compared to a large gear?
  • If we interlock the smallest gear with the largest gear, how do they influence each other?

Background

Gears are wheels with bumpy edges or teeth that fit together. Gear teeth push on each other so they can turn and do work.

Large gears have more teeth than small gears. If a small gear has 20 teeth and a large gear has 80 teeth, we say their gear ratio is 1:4. When the teeth on the largest gear push against teeth on the smallest gear, the small gear spins around four times faster, while the larger gear spins more slowly than the small gear, but with greater force. This is called movement magnification.

Finding the science in your world

Gears are found in many appliances around the house, such as wine bottle openers, analogue clocks, guitar tuning keys and food processors.

In vehicles such as cars, gears are a vital part of steering shafts and engines. Without them, a car wouldn't be able to turn and an engine wouldn't be able to shift 'gears' and engine power.