He-8 Brownian motion using an air table
Published: Tuesday 05 June 2007 - Updated: Monday 28 March 2011
Aim
To demonstrate Brownian motion via an air table.
Apparatus
- Air table
- Air supply
- Overhead projector
Diagrams
Click on pictures to enlarge.
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Air table |
Description
An air table is populated with 20 or 30 small green air pucks and one large puck. On turning on the air supply the small pucks are seen to jostle around and impart a series of small impulses to the larger slower moving puck. If one concentrates on the large puck it will be seen that it follows a random walk, the net effect of all the random collisions is to increase its distance from its starting point.