MHB Measuring Hollow Sphere Diameter with Compass & Ruler

jmprada
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Using only a compass and a ruler, how can we measure the diameter of a hollow sphere?
 
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jmprada said:
Using only a compass and a ruler, how can we measure the diameter of a hollow sphere?

Hi jmprada! ;)

Here's my attempt.

We use the ruler to draw a straight line on the inside of the sphere.
The line will go all the way round and form a great circle.
Repeat and draw a second great circle.
Those 2 great circles will intersect each other in 2 points.
Measure the distance between those 2 points and we have the diameter.
 

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