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Old 10th March 2014 | 07:41
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cwatters
 
Joined: Dec 2001
Posts: 1,389
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From: England
I and one other were taken to task by Skipness One Echo and others for stating that objects of the same size but different densities (eg a basketball and an identical one filled with concrete) would not hit the ground at the same time, dropped from say 35000 feet in an atmosphere.
You are correct. When they reach terminal velocity Drag = weight. If the shape is the same the only way for drag to be different is if the velocity is different.

They would be correct on the moon..
https://www.youtube.com/watch?v=5C5_dOEyAfk

EDIT: should be easy to prove by dropping a table tennis ball and something the same size like an egg...or perhaps not an egg as that's streamlined :-)
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