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To: JoeProBono
Common sense dictates that larger raindrops should fall to the ground faster than smaller ones because they weigh more and can better overcome wind resistance.

I thought Galileo debunked this kind of reasoning with an experiment involving a large sphere and a small sphere dropped simultaneously from a tower.

3 posted on 06/15/2009 6:31:38 AM PDT by Bloody Sam Roberts (The code word for the new racism is "diversity.")
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To: Bloody Sam Roberts

With something as light as a raindrop, the thickness of the atmosphere comes into play. A 100lb cannonball would fall faster (eventually) than a 100lb human, because they have different terminal velocities, since humans have higher wind resistance than cannonballs.


4 posted on 06/15/2009 6:35:57 AM PDT by Little Pig (Is it time for "Cowboys and Islamofanatics" yet?)
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To: Bloody Sam Roberts

As you increase mass, inertia increases proportional to force, so the same gravitational constant applied to objects of two different mass will result in the same acceleration... ALL OTHER THINGS BEING EQUAL.

However, as an object accelerates, the amount of friction it creates by passing through the air increases. So the force (which causes further acceleration) stays constant, but resistance to that force (which opposes further acceleration) increases with speed. Eventually, resistance equals the gravitational force, and you reach a constant speed, where acceleteration = 0. This is called terminal velocity.

Although in Galileo’s case, this difference was too small too measure, so the experiment worked; he chose two objects with similar amounts of resistance. Had he compared the rates at which a feather falls to that of a ball, you can surmise from your own experience that wouldn’t have worked.

In Galileo’s case, the two balls each experienced small enough levels of resistance that the resistance was insignificant. As the fall for a longer time, and the difference in size increases, the resistance becomes more significant, to the point where tiny rain droplets have significantly slower terminal velocities that huge rain droplets.


6 posted on 06/15/2009 6:44:08 AM PDT by dangus
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