Upthrust
Properties of Matter

Floating Egg

Enrichment Activity for 5-11 11-14


What you need

  • A raw egg
  • Glass of water
  • Salt
  • Fresh water

Instructions

  1. Fill up a glass with water until it's about half full. Then add four tablespoons of salt and stir until dissolved
  2. Put the egg in the glass. The egg should float
  3. Gently pour fresh water into the glass. The egg should start to sink
  4. Add just enough water so the egg is floating in the middle of the glass

Results and Explanation

Adding fresh water dilutes the salt water and reduces the amount the water lifts the egg.

Upthrust
is a special case of Force
appears in the relation Upthrust = Weight of Displaced Liquid
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