Centripetal Force
Forces and Motion

Swinging Coat Hanger

Enrichment Activity for 5-11 11-14


What you need

  • A metal coat hanger
  • A pound coin
  • A file

Instructions

  1. Carefully pull the coat hanger out of shape until it forms a square. Bend the hook so that it points towards the newly-formed corner and file the end flat
  2. With the coat hanger on one finger, balance the coin on the hook. This might take some patience!
  3. Once the coin is in place, start swinging the hanger back and forth. Can you get the hanger to swing in a complete circle without the coin falling off?

Results and Explanation

The circular motion of the hanger means that a centripetal force acts to keep the coin firmly in place while you’re swinging

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