Does Density Affect Falling Object Speed?

AI Thread Summary
When two objects of the same shape and size but different densities are dropped from a height in the presence of air, they will not land at the same time due to air resistance. The heavier object will typically fall faster because it can displace air more effectively than the lighter one. This phenomenon does not contradict Galileo's principle of free fall, which assumes no air resistance. The discussion highlights a common misunderstanding about inertia and air resistance in physics. Overall, the impact of air resistance on falling objects is a nuanced topic that can lead to different outcomes based on density.
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Disclaimer: Dont hurt me, I am not exactly a physics nut or anything, and what I am about to say has probably been figured out, its just that I thought of it, and I never heard anything of it before, soooo...

Problem:If two objects were dropped from a height with the same texture, shape, size, and dropping conditions(this wouldn't be in a vacuum), but with different densities, would they land at the same time.

Probable answer(pounded into our heads by 4th grade science teachers)
Yes, they will land at the same time, prooved by gallileo(sp?)

-MY- answer: no, for the heavyer sphere would break the the inertia of the air better than that of the less dense sphere.

I repeat that most likely this is already known, but no one I asked around here(where I live) got that answer, even my brother who is a freshman at CMU studying physics, so I thought it was a good Idea if he didnt get it.

Erm... Yeah... :rolleyes:

(First Post!)
 
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Welcome to PF.
You are correct, if you include air resistance in the model (that's the "scientific" term), then the heavier ball will land first (it's usually too tiny a difference to measure, though).
Do not use the terminology "break the inertia" about this phenomenon, it is unclear what you mean by it (I made the most favourable interpretation of that term).

However, you do not contradict Galileo, because he was talking only about free fall, i.e-, when air resistance is absent from the model.
 
Sorry :C
when I said "break the Inertia" I meant the fact that the air wasnt moving until the heavyer ball shoved it out of the way. Ah well. I figured as much.

Thank you
 
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I think it's easist first to watch a short vidio clip I find these videos very relaxing to watch .. I got to thinking is this being done in the most efficient way? The sand has to be suspended in the water to move it to the outlet ... The faster the water , the more turbulance and the sand stays suspended, so it seems to me the rule of thumb is the hose be aimed towards the outlet at all times .. Many times the workers hit the sand directly which will greatly reduce the water...
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