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[Draco18s]

Whoever said anything about the plane being heavier but people who weren't paying attention? This was about WWII pilots, none of whom ever did battle in an arena with no atmosphere. Further more, the stated reasons for the pilot not carrying on a short distance from his aircraft were "density" and "aerodynamic forces." You could do the hammer and helium balloon experiement on the moon, but that doesnt mean it would work on Earth.

I take it that reading comprehension wasn't your forte:

>>>>Gravity for example ?
>>>The plane and the pilot fall at the same speed.
>>The plane, being much denser than the pilot, would fall much faster.
>The weight of an object doesn't affect it's rate of descent,which is consistent all the time. See the hammer and feather experiment.
Cue someone not knowing WTF the "hammer and feather experiment" is (it was DONE ON THE MOON)
Cue me informing them of this fact
Cue you being dumb thinking I'm talking about AIRPLANES on the moon.
Cue thread derailing derailing derail.

[10ebbor10]

No, lets go back to spheres for a minute. Lets say I get a metal one and a latex one, both about 1m radius. And this is magic latex that wont deform. They are both hollow and I fill them both with helium. They both hit the ground at the same time?

lol, the 2nd one will never hit the floor, so it has no place in a freefalling experiment.

Just read this:
http://www.ehow.com/list_5761172_ball-drop-science-projects.html

So density does matter then?

I think we should quit thread-jacking this topic now.

As long as we're talking about falling objects, density doesn't matter. (Unless you're taking other factors into account, like friction and air currents.)

Also, no stopping the thread derailing: Someone is being wrong on the internet.

But yeah, just read the link, additionally look for information about Galileo, who discovered this strange fact. (He's the one who invented the two balls experiment)

[Rose]

Here's the thing. We /are/ taking into account air friction and lift, because we're talking about somebody stepping out of a plane, both of whom have drag, and one of whom has lift.

[Xinvoker]

Here's the thing. We /are/ taking into account air friction and lift, because we're talking about somebody stepping out of a plane, both of whom have drag, and one of whom has lift.

Yes and their trajectories will be different because of that. But not because of different mass or densities.

[thobal]

Okay, this is my last attempt.

Isnt that more or less Battlefield series?

Realistic

Not, jump out of plane, get rocket launcher, reboard midflight. I meant something more akin to a flight simulator, with failing engines and such.

What was really stopping a WW2 pilot from doing that? Other then sanity.

Enter me saying the relative densities of objects have a great effect on the falling rates of objects in an atmosphere.

Enter a vast amount of irrelevant whargarble about how stupid I am for not realizing that the weights of objects have no effect of their rate of fall, totally ignoring the fact that they were the ones that brought up weight in the first place. Sanity deserted them as they began to gibber about how density has no effect on an object falling in air.

tl;dr We were talking about airplanes when people began talking about objects in a vacuum so I thought they were confused. I tried to inject a bit about balloons to gently bring the conversation back to Earth.

Because differences in density can effect trajectories, take the example of the cannon ball and the balloon.

/threadjack

The B-17 series has bits about engines failing(oil leaking, fuel leaking, crew management), but is more of a bomber simulator(in old game and really old DOS game varients). I haven't played the Il-2 games, but have heard they also have complicated damage models.

[Sirus]

How the hell did you guys go off on a two-page derail? O_o

[thobal]

GEE, ISNT THAT OLD MICROPOSE GAME B-17 COOL AND JUST THE KIND OF GAME THAT GUY WANTED?

[miauw62]

I want a  game that realistically simulates dropping all kinds of airplanes too.

[10ebbor10]

The relative densities have no effect on the objects, but the mass (Weight indicates the strength of the gravitationall force on the object ) do. (A little, mostly considering friction and air movements.).

Example, the two balls experiment. One drops two balls, one made from Iron, one from wood. The balls are of equal size, but different mass. Therefore, there densities are also different. Now if you drop these balls, they will hit the ground at the exact same moment.

Therefore, a difference in density does not impact falling speed. Q.E.D

Now seeing as we just conveniently ignored friction in the previous experiment, let's see what happens then. Both objects would get an equal amount of friction, but considering one objects mass(not density, density isn't important) is larger, it's momentum is too. This would mean that that object would slow down a little less, meaning that it would hit the ground faster.

However, this effect is often neglible. Also, as stated before, it has nothing to do with the objects densities, only with it's mass. The only way  for the density to be relevant is for when it either impacts the mass of the object, or the objects size (and therefore the amount of friction).

Say let's work out a practical example. We have two objects, one having a density of 2 kg/dm³, the other of 4kg/dm³. Both objects are 1dm³ large. Let's also assume that both objects are not hampered by friction, because that is hard to calculate.

Since the energy of the momentum is equal to the energy off the fall, we know:
(m*v²/2)=m*g*h (m=mass, v=speed, g=gravitational force, h=height)
So, when we fill that in:
First object
(v²*2kg/2=2kg*1m*9.81/kg*m)
(v²*2kg/2=2kg*1m*9.81/kg*m)
(v²=2*9.81N)

Second object
(v²*4kg/2=4kg*1m*9.81/kg*m)
(v²*4kg/2=4kg*1m*9.81/kg*m)
(v²=2*9.81N)

Q.E.D.: Two objects without external influences fall at equal speeds, regardless of their relative mass or density.

Now if an other external force(for example the wind) would want to influence the objects path, this calculation applies
v²*m/2 = Energy required for the speed chance v)
As you can see, m stands for mass, not density. Therefore, density doesn't influence an objects path, not directly through gravitationall force, nor indirectly by using external forces.

Q.E.D.

How the hell did you guys go off on a two-page derail? O_o

Someone was being wrong on the internet

[Rose]

density is a function of mass and volume. more density means more mass and/or less volume. Less volume means more drag, and more mass means more momentum, and more force due to gravity, therefore density has an effect.

[thobal]

see above


Example, the two balls experiment. One drops two balls, one made from solid Iron, one a latex membrane filled with gaseous helium. The balls are of equal size, but different mass. Therefore, their densities are also different. Now if you drop these balls, one will promptly fall to the ground while the other floats idly upwards.

It is thus shown that density has a quite obvious effect on the behavior of objects in a gaseous medium.

Sorry, just had to fix that for you.

[FuzzyZergling]

Spoiler: Off-Topic (click to show/hide)

What does Q.E.D. stand for?

I wish for a Skyrim-style game set in the DF universe.

[Xinvoker]

Looks like these particular wrong people on the internet will have to remain wrong, since they ignore mathematical proof.

[Rose]

Quod Erat Demonstratum, means "Is also in agreement"

[thobal]

Spoiler (click to show/hide)

Looks like these particular wrong people on the internet will have to remain wrong, since they ignore mathematical proof.

Let's also assume that both objects are not hampered by friction, because that is hard to calculate.

Don't insult my intelligence. That little assumption you made means you're ignoring the air altogether when this entire argument is about the effects of air on the movements of objects.

Your mathematical proof is irrelevant because it completely ignores the question.

VERY OFF TOPIC