Gravitational Force (Weight)
Forces and Motion

Water Fall

Enrichment Activity for 5-11 11-14

What you need

  • A plastic cup
  • A pair of scissors
  • Some water


  1. Cut a hole in the bottom of the plastic cup about 1cm in diameter, making sure that your finger can cover it (ask an adult to help with this)
  2. Cover the hole with your finger and fill the cup with water. Make sure you’re somewhere that can get wet
  3. Drop the cup, removing your finger from the hole as quickly as possible

Results and Explanation

The water stays inside the cup despite the huge hole! The cup and the water are falling at the same rate due to gravity so they hit the ground at the same time.

These experiments have not been specifically safety tested for home use but we believe them to be safe if the instructions are followed. Adult supervision or direction is recommended as appropriate. All experiments are carried out at your own risk.

Gravitational Force (Weight)
is a feature of the Rigid Body Model
is a special case of Force
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