8A05.30 - Eratosthenes' Measurement of Earth's Radius

Code Number:
Demo Title:
Eratosthenes' Measurement of Earth's Radius
Measuring the Radius of the Earth
Area of Study:
Eratosthenes' Model.

Place the model so that one of the pillars is pointed at the light source and gives no shadow.  Bend the cardboard and show that the other pillar produces a shadow whose size depends on the radius you have produced by bending the cardboard.

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