Forces and Motion

Dancing Pop Can

Enrichment Activity for 5-11 11-14

What you need

  • An empty fizzy drink can
  • Some water


  1. Pour about 100ml of water into an empty fizzy pop can
  2. Tip it slightly to one side and balance it so that the two parts of the bottom rim are touching the table
  3. Once the can is stable, give it a gentle push and it will pirouette!

Results and Explanation

For something to balance, its centre of mass has to be above its point of support. Water can flow which means that as the can pirouettes, the water moves and the centre of mass always stays above where the rim touches the table.


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