How to weigh air

Supplies needed to test if air has weight


To show that air has weight


  • two balloons
  • tape
  • ruler or yardstick
  • string
  • pin


Have your students inflate the balloons until they are the same size; then tie them shut. Have them put a piece of tape on one of the balloons near the opening, and use 2 pieces of string to tie one balloon to each end of the ruler or yard stick.

Have them tie another piece of string around the centre of the ruler and hang it up so that the two balloons are balanced and they do not rub against a wall.

Take the pin and make a small hole in the tape on the one balloon. When you step away, make sure the two balloons are still balanced.


The balance of the stick favours the heavier, inflated balloon on the right because it contains more air than the uninflated balloon on the left

The balance changes as the air in the one balloon leaked out and the balloon became lighter.


Air has weight.

Other games and activities

Report a problem or mistake on this page
Please select all that apply:

Privacy statement

Thank you for your help!

You will not receive a reply. For enquiries, contact us.

Date modified: