Static Force vs. Dynamic force
HTML-код
- Опубликовано: 13 сен 2024
- Simply put, static force is the force a non-moving object exerts on another object that supports it. (Static = not moving).
Dynamic force is the force a moving object puts on an object when it hits it. (dynamic = moving).
These are very different things, and yet they are often conflated in 9/11 theories. People will say that since the lower part of the building could support the upper part, then it should also be able to stop it when it was falling.
The problem is that "support" relates to a static force. "stopping" relates to a dynamic force. Dynamic forces from a falling object are vastly higher than static forces from the same object.
In this example there's a support structure (a can) that easily supports 100 pounds. Here it supports a 10 pound hammer.
When I drop the hammer on the can, it is crushed, and the hammer hardly even slows down. This shows the dynamic force is much more than the equivalent of 100 pounds, but it's only coming from a 10 pound object.
And in this case it's only falling two feet. The falling parts of the World Trade Center towers fell much more, and so the force was multiplied much more.
Seeing that can crush perfectly in slow motion was so satisfying 😌
Excellent demonstration and explanation of the difference betweet static and dynamic load.
The most perfect can crush ever
Nice shot, how many takes did that require to get the perfect squish?
Two. The hammer is pretty heavy (10 lb), just needed to be lined up vertically.
The can has a static strength of 100 pounds (max). The energy you applied to the can converts from E = mgh (potential) to full kinetic energy upon impact from 2 to 3 feet. In other words, if you are weightlifting don't drop the weights, instead lower them slowly or else you may end up with torn muscles like the crushed can.
Thank you sir
great thank you
Hi, Mick. What if you were to first set the sledge on top of the can, then slowly press downward with an increasing amount of your body weight to increase the load. Is that considered static or dynamic?
I've always considered it to be dynamic as well in that the force changes over time, just not in the way that you had demonstrated. Where I get confused is that equipment such as a hydraulic press basically applies force in the same way that I just described, yet I often see that referred to as a "static forging force".
what I've never had anyone articulate to me is whether there is a fundamental difference between an EQUAL dynamic and static load.
in this example we have a #10 static load and a ~#110 dynamic load... would a #10 static and dynamic load have the same affect on the object?
Not really, a dynamic force varies over time, so the effect is different. Of course establishing a static force involves dynamic force. But if you start digging in it’s just all force and time,, but complicated.
@@MickWest I appreciate the hell out of the response.
So the top 10% of WTC Tower 1 was floating on a giant air pocket before it came crashing down? Got news for you: there were still core and support columns which would've significantly slowed down the collapsing top portion. The lower 90% of the structure was still intact with some 90,000 tons of structural steel, and over 200,000 tons of concrete. How does this compare to dropping a sledgehammer on top of an empty aluminum can? This is an outlandish comparison.
The WTC buildings did not collapse in such a manner. Thick structural steel and the core columns were BLOWN OUT a hundred yards into neighboring structures, which allowed the top section of the buildings to collapse through what should've been the area of most resistance. They also collapsed near the rate of freefall. This completely defies the Law of Conservation of Momentum which is a fundamental law of BASIC PHYSICS.
Maybe you'll fool the layman who doesn't know anything about the explosions, the ejected steel, the molten steel, the pulverized concrete, the suspicious collapse of WTC 7 (which wasn't hit by aircraft), or the iron spheres and evidence of military-grade nano-thermite (some of it unreacted), but you're not going to fool people who have researched the collapses, and know they were controlled demolitions.
The tons of rapid moving rubble stripped the floors away from the columns. Now lacking lateral support, the columns failed AFTER the collapse wave had PASSED them.
The steel girders in wtc7's inner core were attached to the support columns with only 4 bolts.....that's not very strong.
The twin towers had almost Zero resistance to vertical kinetic energy.
Engineers only design buildings to have ''dead load'' and ''live load'' vertical resistance.
You can't stop dynamic amplification unless you have a transfer floor or alternate load path etc.
Name just one building in the world that has been designed to withstand a 12 or 29 story vertical impact?
OMG I love you "twufers". PLEASE learn how the "hollow tube" structures work before you embarrass yourself)))
superrrrrrrrrrrrrrrrrrrr
the coca cola writing wasn't touched
What would be a good definition for grade seven for dynamic load and static load?
I'd use essentially the simple definitions of static and dynamic (unchanging and changing) with the most obvious examples.
Static load is the forces that don't change, the weight of the building.
Dynamic load is the forces that do change, the people and the wind.
Then you could have an interesting discussion of if snow is a static or dynamic load. Then gradually and suddenly applied loads. HOW dynamic is any given load, and how does it turn into a static load.
Yes, but it slows down.... :)
@Bob Loblaw The actual collapse was not simple. But basically at some point there's not enough support for the top, so it starts to fall and break up. Not like a sudden drop, but once it started there was no stopping it.
Is dynamic loading the same as impact loading?
I didnt get it.. I think it became a potinotal energy after droping it.. Where is the daynamic now!!!
I'm talking about force, not energy. There's two main forces at play 1) gravity, and 2) intermolecular forces that resist (essentially) the Earth collapsing into a black hole (and by extension, keep the can (and the ground) from being crushed. In the static state, the molecular forces resolve to the "normal" force that balances gravity (i.e. a net up vector equal to the down vector of gravity). In the dynamic state the force of the moving hammer is too much for the molecules in the can, so they fail in various directions, causing buckling.
@@MickWest thank you for your explaination. ❤️
This is useful to present a concept but unfortunately the physical system of a huge weight dropped from a large height above a relatively weak structure is very different from that of a building. A closer analogy would be to put some paper inside the can, set fire to the paper, then show the can spontaneously crushing itself symmetrically at free fall. Seems beyond belief that this could happen.
Physics don't scale. You can't prove most stuff with minuatures. But this video clear demonstrates the huge difference in force created when a moving object is being stopped versus when something is just supporting the same weight.
As WTC, well we did see what happens when jet fuel and office furniture and stuff burn for hours weakening and distorting the floor trusses and warping the outer and inner columns. Part of a floor separates from the vertical supports and then it was all down hill from there....
He was holding on to the hammer. When he was crushing the can if he was the hammer would have fell either side ways or to the front if no one was holding it
No, I just dropped it.
Nice try!
HAHAHAHA