Do heavier objects fall faster?

Blinkz

Blinkz

Blinkz

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Right having a great Saturday night discussion with my house mates. Basically we are talking about gravity. We are assuming no friction, air resistance etc

I think that objects will fall towards each other at the same rate. My thoughts on this is that as the mass of an object increases the gravitational force increases, however the increase in mass also increases the force needed for the same acceleration, using F=ma

However my mate says this is wrong and that heavy objects fall faster. His example of this is the earth and the moon. The acceleration towards the earth is bigger then the acceleration on the moon.....

any thought??
 
Go to the top room in your house, get a feather and an apple and drop them both out of your window and report back the results. I think you'll be surprised. :p
 
Are we talking about things falling due to gravity, or how the gravitational pull of two objects interact? If the former, then everything falls due to gravity at the same speed (aroung 9.81ms-2)
 
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No all objects fall at the same speed regardless of their mass in an ideal system. On Earth a feather falls slowly due to it's increased resistance to the air and this applies to other objects.

However if it's two planet like objects the force which they attract with is

GMm
---- = F
r^2

which means that the biggest object will move towards the smaller object slower than the slower object moves towards the bigger object but the force is the same.
 
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In air, the surface area dictates the speed at which objects fall. A ball of paper and a ball of paper with a piece of lead inside will fall at the same rate as long as they are the same size.
 
No.

Apple + Feather dropped in a vacuum, both land at the same time because the acceleration due to gravity is the same for both objects.

Blinkz said:
However my mate says this is wrong and that heavy objects fall faster. His example of this is the earth and the moon. The acceleration towards the earth is bigger then the acceleration on the moon.....
Click to expand...
That is nonsense and correct at the same time. He can't use the earth and moon as an analogy. But the acceleration due to gravity is different on the moon than the earth, because of the mass difference (earth heavier).
 
They'll fall at the same speed. Anything else is just incorrect (under the assumptions made in the OP anyway).
 
Like I said guys this is all a theoretical situation, so no air resistance or anything. The acceleration between the objects is relative to each other, not from another observation, if that makes sense.

Any actual proof to the answer would be great!
 
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Blinkz said:
Like I said guys this is all a theoretical situation, so no air resistance or anything. The acceleration between the objects is relative to each other, not from another observation, if that makes sense.
Click to expand...
Don't bring Relativity into this please! :(
 
Blinkz said:
Right having a great Saturday night discussion with my house mates. Basically we are talking about gravity. We are assuming no friction, air resistance etc

I think that objects will fall towards each other at the same rate. My thoughts on this is that as the mass of an object increases the gravitational force increases, however the increase in mass also increases the force needed for the same acceleration, using F=ma

However my mate says this is wrong and that heavy objects fall faster. His example of this is the earth and the moon. The acceleration towards the earth is bigger then the acceleration on the moon.....

any thought??
Click to expand...


Open the top floor window. Throw out...

The fat housemate

The thin housemate

Time the results.

And then you can get some new fun mates as well.
 
hendrix said:
No.

Apple + Feather dropped in a vacuum, both land at the same time because the acceleration due to gravity is the same for both objects.

That is nonsense and correct at the same time. He can't use the earth and moon as an analogy. But the acceleration due to gravity is different on the moon than the earth, because of the mass difference (earth heavier).
Click to expand...

surely if everything was in a huge vacuum, the apple would fall towards the earth faster because the gravitational pull of the apple on the earth is greater than the gravitational pull of the feather.

but you're not going to notice.
 
Rebelius said:
surely if everything was in a huge vacuum, the apple would fall towards the earth faster because the gravitational pull of the apple on the earth is greater than the gravitational pull of the feather.

but you're not going to notice.
Click to expand...
Same experiment was actually done on the moon (where we did land :p ) and showed the same result. The "Gravitational Pull" is a force in this respect, and yes it is different, but so is the mass. The ratio (F/m) of the Feather and the ratio of the apple, are both the same and are equal to the acceleration due to gravity a. Newton <3

Edit: I'm off to Beer Kellar. Physics > Non-sense
 
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