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Soap bubble lunacositudiness

That is indeed bizarre. Haven't any of those kids ever even played with soap bubbles?? That's on par with KKKilltown thinking you need electricity to run a barbeque.

For what it's worth, how a soap bubble behaves in atmosphere depends almost entirely on wind, and the rest is due to temperature. If there's no wind, a large bubble containing heated air will actually rise, though being hotter it will evaporate its soap-film skin faster, and pop sooner. In wind, its speed is dominated by the wind, case closed. Its terminal velocity is at most about one meter per second.

I actually wrote a thesis on soap films. I dare anyone to challenge me on this topic.
 
Also,

http://en.wikipedia.org/wiki/Terminal_velocity

The equation for terminal velocity is very clearly dependant on mass. His assertion that a normal brick and a brick of lead (or whatever makeup he chooses) will hit the ground at the same time dropped in air is completely and utterly false.

The heavier item will have a higher acceleration, and a higher terminal velocity.
 
An even better link for him...

http://www.glenbrook.k12.il.us/GBSSCI/PHYS/CLASS/newtlaws/u2l3e.html

In situations in which there is air resistance, more massive objects fall faster than less massive objects. But why? To answer the why question, it is necessary to consider the free-body diagrams for objects of different mass. Consider the falling motion of two skydivers: one with a mass of 100 kg (skydiver plus parachute) and the other with a mass of 150 kg (skydiver plus parachute). The free-body diagrams are shown below for the instant in time in which they have reached terminal velocity.
Click to expand...

This is a great site because it's meant for k-12 kids. It even has pictures of guys with parachutes and helicopters (not black though!) and elephants!

He should be able to follow it.
 
Anti-sophist said:
An even better link for him...

http://www.glenbrook.k12.il.us/GBSSCI/PHYS/CLASS/newtlaws/u2l3e.html



This is a great site because it's meant for k-12 kids. It even has pictures of guys with parachutes and helicopters (not black though!) and elephants!

He should be able to follow it.
Click to expand...

He actually linked to that site in the Loose With the Truth thread at issue in support of his contention that a soap bubble and a golf ball will both hit the ground at the same time. I kid you not.
 
LashL said:
He actually linked to that site in the Loose With the Truth thread at issue in support of his contention that a soap bubble and a golf ball will both hit the ground at the same time. I kid you not.
Click to expand...

Yes. He insists that the shape is the only factor in fluid resistance or terminal velocity, ignoring completely the mass term in all those equations.

Despite having it pointed out to him more than once.

Brilliant!
 
Arrowhead said:
Anyone who's seen the video of the south tower go down, will not dispute the almost total free fall nature of the "fall". It peeled away, and even seemed to accelerate as it went down. I call it "the foot of God hypothesis" absent the use of demolition explosives.
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Indeed. It almost seems to... accelerate.... What a crazy concept. It's not entirely new, though. Isaac Newton called it "gravity". He got there first, as well, so his names sticks. Sorry "foot of God".


These guys are seriously unbelievable.
 
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Anti-sophist said:
Indeed. It almost seems to... accelerate.... What a crazy concept. It's not entirely new, though. Isaac Newton called it "gravity". He got there first, as well, so his names sticks. Sorry "foot of God".


These guys are seriously unbelievable.
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Hey, at least he has a hypothesis!!

It woz god wot dun it.
 
The truly sad part is that they *almost* have it, and just can't quite piece it together. From Animal's post, they get some important Formulas:

Animal said:
Using Newton’s law again: "F = ma". Now we have the force of gravity "mg" trying to speed the object up and the force "r" trying to slow it down. The total force is therefore "mg-r" so: "mg-r = ma" Now if we solve for "a" we get "a = g - r/m". If the mass is rally big, the second term on the right hand side of the equal sign "r/m" will be small compared to "g" which means that we can ignore it and write "a = g" just like when there is no air to worry about. If the mass is small, we can’t ignore the "r/m" part, and the acceleration "a" will be smaller than "g" since "a = g - r/m". So, the answer to your question is that if you take air resistance into account, then the heavier sphere will reach the half-way point first. .
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Arrowhead chimes in with:
Arrowhead said:
Now, in terms of resistence as an impediment to a falling object or objects, which offers greater resistence, steel, or air?
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He's SO CLOSE, you almost have to be proud of him. He think's it's an "Ah, HA! Gotcha" moment for the truthers, But the question isn't "Which offers greater resistence" but "how much resistance does the lower part of the Towers offer?" - Can the resistance of an individual floor be enough to make r/m (in the a=g - r/m forumula) a meaningful number? 'cause our mass is STUPIDLY huge. If that term of the equation isn't meaningful, then a=g, which is pretty close to what happened to the towers. And if one floor doesn't offer enough resistance to make a difference, then the speed of the collapse shouldn't be surprising.
 
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More of water_bender misconceptions of air resistance.

given the right amount of resistance, regardless of the objects size or weight, the object can actually negate the effects of gravity and stay aloft. we should all be aware of this phenomenon, as it is what makes things like airplanes fly.
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I know it's not nice but with him being so sure of himself.
:dl:
 
Grundar said:
More of water_bender misconceptions of air resistance.


I know it's not nice but with him being so sure of himself.
:dl:
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Well, if he had said "hot-air balloon", he'd be right. I just don't know what buoyancy has to do with falling steel and concrete.
 
Horatius said:
Well, if he had said "hot-air balloon", he'd be right. I just don't know what buoyancy has to do with falling steel and concrete.
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Not even then, because as you said thats buoyancy and not air resistance.

/Hans
 
Grundar said:
More of water_bender misconceptions of air resistance.


I know it's not nice but with him being so sure of himself.
:dl:
Click to expand...

He was partially right about objects being able to float. Even people can avoid gravity. Anyone with any sense knows all you have to do to fly is throw yourself at the ground and miss.
 
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