Is Free Fall Possible Without Air Resistance?

AI Thread Summary
Free fall occurs when the only force acting on an object is gravity, which means air resistance must be absent for true free fall. In environments with air, such as falling through the atmosphere, air resistance and upthrust counteract weight, resulting in a non-zero resultant force. The discussion highlights that while objects like geosynchronous satellites experience free fall without air resistance, objects falling through the atmosphere do not meet the strict definition of free fall due to the presence of air resistance. The conversation also touches on the subjective nature of definitions in physics versus common usage. Ultimately, the distinction between free fall and falling with air resistance is crucial for understanding the forces at play.
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Hey guys,

when an object is free falling, is it still under the effects of air resistance? If it was not under the effects (an environment without air resistance) is free fall possible? (I am looking for an argument that it is under the effects of free fall but all replies will be taken into consideration)
 
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When a body is falling through the air there are three forces acting on it, Weight(W), Friction(F) and upthrust(U).
The resultant force is given by F_R=W-U-F, when in free fall the resultant force is zero. So then the air resistance is still there but the weight is numerically equal to the sum of the air resistance and upthrust.
 
If someone is free-falling off a bridge, there is air resistance. Geosynchronous satellites are in free-fall, and there is no air resistance.

Sounds like a discussion about a definition rather than physics?
 
Yes, it is a discussion about a definition. The technical physics definition is falling where the only force acting on you is gravity. So that means jumping out of a plane doesn't qualify. But definitions are a matter of consensus, so the dictionary has that one in there too.
 
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