Open Letter to Dave Thomas

[Dave Rogers]

If temperature is a measurement of kinetic energy, what is causing the weakening of the mechanical bonds in the steel? The kinetic energy or the measurement of the kinetic energy?

Your question is incorrectly framed, because temperature is not a measurement of kinetic energy, it is a physical property. The temperature is the average kinetic energy, expressed in appropriate units.

Dave

 

[Cuddles]

A large number of uncivil and off topic posts have been removed to AAH. Continuing with this behaviour is likely to result in further moderator action, up to and including suspension or banning.

Replying to this modbox in thread will be off topic  Posted By: Cuddles

 

[GlennB]

A large number of uncivil and off topic posts have been removed to AAH. Continuing with this behaviour is likely to result in further moderator action, up to and including suspension or banning.

Replying to this modbox in thread will be off topic  Posted By: Cuddles

And a number of extremely well-reasoned and informative posts have been excised too. Was it that folks were discussing the nature of heat/temperature within the thread? If so, this has been happening for several pages now but only a recent slice have been AAH'ed.
And it seems extremely pertinent to the o/p, barely 'thread drift' even

 

[Dave Rogers]

So you now agree that when an object is in free fall all the available gravitational potential energy is converted to kinetic energy? Yet here you state:

"your statement that "With a free falling object all the available gravitational potential energy has been converted to kinetic energy" is inconsistent with simple Newtonian mechanics. Clearly, then, you don't understand Newtonian physics. (I'm being charitable here and assuming you're merely incompetent, rather than lying.)"

Unbelievable.

Look, I've had enough of trying to point out your strawman arguments. The simple sequence of events was this:

The shell of WTC7 starts to move downwards at less than freefall acceleration. Some potential energy is converted into kinetic energy, and some into fracture energy. A multi-storey buckle propagates rapidly across the perimeter. The energy from this comes from the initially available gravitational potential energy.

When the columns have completely fractured, the shell drops at near freefall for about eight storeys - the average length of the multi-storey buckle. During this phase, no energy is converted into fracture energy, because the fracture has already happened.

After an eight-storey drop, the shell encounters resistance from the lower structure, and from this point onwards more energy is converted into fracture energy.

However, it is utterly false to claim that "all the available gravitational potential energy has been converted to kinetic energy" in the freefall phase, because a part of the available gravitational kinetic energy was converted to fracture energy before the freefall phase began.

If you'd like to dispute that, please do so. If you prefer to make up statements and attribute them to me, then I won't need to reply; I'll content myself with the knowledge that you're simply demonstrating your dishonesty.

Dave

 

[cmatrix]

We have. We have all the evidence. Everything about the WTC7 collapse points to fire and gravity as being the primary causes of the collapse. The gibbering of incompetents does not constitute contradictory evidence.

Dave

You have all the evidence? Great! Where is the evidence the 2.25 seconds of WTC 7's free fall was caused by buckling? Remember, the gibbering of incompetents does not constitute evidence. If you have no evidence you have a crackpot faith-based theory not science.

 

[Newtons Bit]

You have all the evidence? Great! Where is the evidence the 2.25 seconds of WTC 7's free fall was caused by buckling? Remember, the gibbering of incompetents does not constitute evidence. If you have no evidence you have a crackpot faith-based theory not science.

wtc.nist.gov

Do you accept engineering Finite Element Analysis as a valid means of determining how a structure behaves?

 

[excaza]

You have all the evidence? Great! Where is the evidence the 2.25 seconds of WTC 7's free fall was caused by buckling?

In the NIST report.

Remember, the gibbering of incompetents does not constitute evidence. If you have no evidence you have a crackpot faith-based theory not science.

How's that CD evidence coming along?

 

[cmatrix]

Explosives couldn't remove it without making a very loud bang, and there wasn't one. Thermitics, if they actually worked at all (which they don't), would work by melting the steel, which would weaken it gradually over several seconds, resulting in exactly the same objection to thermitics as you're making to fire. And, of course, all the supporting evidence supports fire.

Dave

All the evidence includes the eutectic reactions ("intergranular melting capable of turning a solid steel girder into Swiss cheese.") and nano-thermite particles in the dust. How does that evidence support fire?

 

[twinstead]

You have all the evidence? Great! Where is the evidence the 2.25 seconds of WTC 7's free fall was caused by buckling? Remember, the gibbering of incompetents does not constitute evidence. If you have no evidence you have a crackpot faith-based theory not science.

I know people will be shocked, but somehow your claiming that the contributers to the NIST are incompetent and that there's no evidence that the free fall was caused by buckling doesn't hold much water. Especially when you claim that you are supported by evidence when you ARE MOST DEFINITELY NOT.

Until you come up with a theory that matches what was observed and the existing evidence BETTER, then I will recognize your trying to chip away at the commonly-held theory so you can insert whatever unfounded tripe you can dream up in its place, with no evidence to support IT, for what it is.

 

[excaza]

All the evidence includes the eutectic reactions ("intergranular melting capable of turning a solid steel girder into Swiss cheese.")?

How exactly do eutectic reactions support CD?

 

[DaveThomasNMSR]

Originally Posted by DaveThomasNMSR
No, you have to consider the energy required to get the ball rolling down the ramp, which involves the angle of the ramp, and the ball's moment of inertia. While balls of various masses and sizes will roll down the ramp at the same acceleration, and while hollow cylinders will likewise have the same acceleration, in general the acceleration is smaller as moment of inertia is larger. A solid sphere beats a solid cylinder beats a hollow sphere beats a hollow cylinder. It all boils down to ratios of mR2

It still has the same net kinetic energy...

For the object falling straight down without resistance, the gravitational potential energy mgh is converted to kinetic energy, 1/2mv².

But for a ball or cylinder rolling down the ramp, with friction making it spin round and round faster, some of the potential energy is converted to rotational (spinning) energy, 1/2Iw², where I is the moment of inertia, and w the angular velocity (radians of rotation per second).

That's how the hollow cylinder loses the race to a solid cylinder, which loses to a solid sphere.

This should not detract from Newton Bit's splendid exposition of temperature vs. heat, nor Dave Rogers' fine discussion about WTC7's buckling columns, nor with excasa's other points, etc. I would caution CM and ergo against committing the false dichotomy flaw - the fact that non-truthers might not agree on everything in no way indicates that truthers are right about anything.

 

[excaza]

For the object falling straight down without resistance, the gravitational potential energy mgh is converted to kinetic energy, 1/2mv².

But for a ball or cylinder rolling down the ramp, with friction making it spin round and round faster, some of the potential energy is converted to rotational (spinning) energy, 1/2Iw², where I is the moment of inertia, and w the angular velocity (radians of rotation per second).

Yes, I'm well aware of what rotational kinetic energy is. Do you have a point? You haven't contradicted anything I've said.

 

[DaveThomasNMSR]

All the evidence includes the eutectic reactions ("intergranular melting capable of turning a solid steel girder into Swiss cheese.") and nono-thermite particles in the dust. How does that evidence support fire?

Where do you get "thermite"? Whatever Harrit et. al. found in WTC dust was no thermite, reacting some 450 degrees centigrade too low.

 

[cmatrix]

Look, I've had enough of trying to point out your strawman arguments. The simple sequence of events was this:

The shell of WTC7 starts to move downwards at less than freefall acceleration. Some potential energy is converted into kinetic energy, and some into fracture energy. A multi-storey buckle propagates rapidly across the perimeter. The energy from this comes from the initially available gravitational potential energy.

When the columns have completely fractured, the shell drops at near freefall for about eight storeys - the average length of the multi-storey buckle. During this phase, no energy is converted into fracture energy, because the fracture has already happened.

After an eight-storey drop, the shell encounters resistance from the lower structure, and from this point onwards more energy is converted into fracture energy.

However, it is utterly false to claim that "all the available gravitational potential energy has been converted to kinetic energy" in the freefall phase, because a part of the available gravitational kinetic energy was converted to fracture energy before the freefall phase began.

If you'd like to dispute that, please do so. If you prefer to make up statements and attribute them to me, then I won't need to reply; I'll content myself with the knowledge that you're simply demonstrating your dishonesty.

Dave

Good grief! Again, the mistake you are making is equating the sum total of GPE with "all the available GPE". It's not the same thing.

Mr. Thomas, you can end this annoying diversion with a simple clarification. Nothing I say will ever convince them.

 

[cmatrix]

wtc.nist.gov

Do you accept engineering Finite Element Analysis as a valid means of determining how a structure behaves?

Exactly where on wtc.nist.gov is the evidence the 2.25 seconds of WTC 7's free fall was caused by buckling? I have been searching for years. If you have no evidence you have a crackpot faith-based theory not science.

 

[excaza]

Nothing I say will ever convince them.

Because it's gibberish.

 

[excaza]

Exactly where on wtc.nist.gov is the evidence the 2.25 seconds of WTC 7's free fall was caused by buckling?

http://wtc.nist.gov/NCSTAR1/

I have been searching for years.

Then you have either a reading comprehension problem, an intelligence problem, or both.

 

[Edx]

Where is the evidence the 2.25 seconds of WTC 7's free fall was caused by buckling?

Where is the evidence that it was super quiet nano thermite explosives? lol

 

[DaveThomasNMSR]

Yes, I'm well aware of what rotational kinetic energy is. Do you have a point? You haven't contradicted anything I've said.

Just that rotational kinetic energy is not the same as translational kinetic energy. The latter is what is related to linear acceleration.

 

[GlennB]

All the evidence includes the eutectic reactions ("intergranular melting capable of turning a solid steel girder into Swiss cheese.") and nono-thermite particles in the dust. How does that evidence support fire?

Just to keep things clear here ... have you given up on the demolition by explosives theory you were proposing earlier (the one with blast mats) and moved to demolition with incendiaries?