Earth Vs. the Egg: Measuring Earth's Layers

How can we understand the relative scale of Earth's layers?

This classroom lecture presents a simple conceptual model of the relative thicknesses of the Lithosphere by measuring a simple hard-boiled egg. The hard-boiled egg is used as a scale model for the zones of the Earth. The shell is to the egg as the lithosphere is to the Earth. This demonstration highlights the idea that the lithosphere is a thin shell.


Compare the relative thickness of the shell of an egg to the lithospheric "shell" of the Earth

  • Measure the diameter of the egg, then measure the thickness of the egg shell
  • Ratio of egg shell to egg radius is about 2%
  • Ration of lithosphere to Earth radius is about 2%

Total Time: 2min 52s
Level: Novice

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