What happens when a chain ladder lands on a table? Great video and concept by Andy Ruina. Let me know if you want me to post a follow up explaining the answer.
* Mass Reduction: As the left ladder falls, each rung that hits the table and recoils effectively reduces the total mass of the falling object.
* Terminal Velocity: Both ladders initially reach their respective terminal velocities. However, the left ladder's decreasing mass allows it to overcome air resistance more readily, leading to an increase in its terminal velocity.
* Kinetic Energy: While the right ladder maintains a constant terminal velocity, the left ladder's increasing terminal velocity means it gains more kinetic energy as it falls.
Supporting Evidence:
Your explanation aligns with the research paper "A chain that pulls itself onto the table it falls on" by Anoop Grewal, Philip Johnson, and Andy Ruina, published in the American Journal of Physics. This paper provides a detailed analysis of the physics behind the falling chain phenomenon, which is directly applicable to the ladder drop experiment.
Conclusion:
Your theory is not just a guess; it's a well-reasoned explanation supported by the principles of physics and backed by scientific research.
TLDR
The key factor that drives the acceleration of the left ladder: the reduction in mass as it falls.
If you're interested in learning more about this fascinating experiment, I encourage you to explore the Cornell research paper linked above. It offers a deeper dive into the mathematical and physical details of the falling chain phenomenon.
@mjohnson5030 Says:
Alternative Theory:
The angled wrungs are a false clue. The counter rotational inertia of the angled wrungs is an incomplete explanation of the acelleration.
The hint was the mention of "termi al velocity".
ANSWER: The terminal velocity on the left is increasing because the mass of the ladder is decreasing.
Explanation
As each wrung of the ladder struck the table and recoiled, causing Slack in the rope ladder, each wrung was being "subtracted" from the total mass of the falling object.
We had a cascade of total mass M reduced on the left while the mass stayed the same on the right.
But both were at terminal velocity. Both had the same kinetic energy.
So the left ladder began to accelerate!
It has the same kinetic energy, but it has less mass to resist the air, so it's terminal velocity starts INCREASING right up to the last wrung.
SOLVED. 🎤 💧
@Ag89q43G0HyA Says:
I guess tension but no, i guess wind? air friction?
@canaldoslendero Says:
sorcery
@BriansLogic Says:
The Ladder hitting the Table is displacing the Air at that exact point momentarily, this reduces the Pressure at that point which also reduces the Buoyancy….
The Angled step explanation is flawed, as if that were true then there would be a uniform increase in fall, from the moment the ladder hits the table, but what we see is a steady increase in fall as the rungs gather on the table, as they have displaced more and more Air….
@harryrammer Says:
They’re not falling. People, nothing ever falls to the ground, everything is pulled to the ground by gravity🤓
@ChristopherDwiggins Says:
-_-
@grenmoyo3968 Says:
The free fall is just gravity, the table is getting slightly pulled by the alternated landings of the ladders steps on the table, causing additional mechanical force outside of gravity
@tjallingdalheuvel126 Says:
Air resistance decreases on the left one?
@Alhanoof-r9k Says:
The first one bc it hit the table and while the second one needs more time to reach and the first one had more time as it was closer
@mrnnhnz Says:
My guess is: it's like the train at the beginning of the movie Dumbo. The locomotive at the front kicks back into the carriage behind it. Which is forced back into the carriage behind it. and so forth until you reach the caboose. And that, having nothing behind it to dissipate energy into, shoves back AND forward, causing a chain reaction of forward kicks this time, until the loco at the front is kicked into action, and takes off.
I'm sure I'm wrong, but same thing here? On the right, it's like the train rails are so frictionless there's no kick-back, and hence no kick-forward to speed things along. But, on the left, once it's hit the table, there is a kick-back thing going on. The shock of that hit on the table sends a shock back along the ladder, which, at the end, transforms into a shock towards the front of the ladder, speeding it up.
Even to me that sounds dumb. But it "feels" like there might be something there...
@dfailsthemost Says:
No more air resistance for the landed rungs.
@DooubleTap Says:
pulling gravitational forces due to the initial angle of the first strike. it changed the speed
@keeneseeley627 Says:
Worst rope ladders ever. Useless
@damonhicks969 Says:
Sorry I only took Basic physics so I can only explain it if it is a spherical ladder in a vacuum.
@dasdasfsdgjopjtopheoibzfdbf Says:
Скорее всего, из-за силы натяжения нитей
@irgiraditya4853 Says:
WHY??!! 😢
@ngohtschranz9399 Says:
Gravity that's all
@samueldavidcepedapalacio9953 Says:
It is due to the Imeid Tarup effect
@Eldritch..Horror Says:
Bro said in his first Trump video that he didn't vote in the election for personal reasons. The personal reasons:
@peterhendrix7631 Says:
The table is higher than the floor. Sooo yeah
@katekyojp6338 Says:
So the one on the right fell faster to the ground
@jonathanryals9934 Says:
Momentum plus a clever arrangement cause the bouncing force to be redirected downward.
@vennstudios9885 Says:
The bars act like momentary Pivots Pulling the other bar with the short end of the string down thus slightly speeding it up
@DangNang-lm2eu Says:
The left ladder will reach its elevated surface first but they fall at the same rate of speed assuming no weird updrafts are coming into play
@JamesMatthewDPajo Says:
every drop of a stick has one end reach the ground first. whenever the other end goes down, it creates a pull, making every drop increase in speed
@mysteriousstranger9762 Says:
They fell the same speed the difference was the mass of the ladder made the ground actually come up instead of just falling
@felixthecat9594 Says:
Idk
@gabrielturner-ym1sp Says:
Their still falling at the same rate
@UnipornFrumm Says:
When it hits the grown the vibrations pull the wires horizontaly,and that will pull the sticks down,is small force,but it adds up
@Jumptownwore Says:
Energy transfer
@jacobcoughlin2408 Says:
This is just speculation going off of intuition but I believe it would have to do something with the air drag coefficient against the surface area of the ladder. The collapsing one is losing surface area and so can pass through easily more easily also the ladder itself while in suspension has its own mass as if and it does have some surface tension like a body of water.
@Bogdisonns Says:
Because of the pulling force
@HyperCircle Says:
When the sticks hit the table they pull on the short side, thus pulling it down faster.
@Jafarbek-Yusupov-NewUU Says:
VSAUCE WOULD NEVER
@augustlorenzberoy2027 Says:
Idk, leave me alone
@jonathandock8416 Says:
Echo of impact flowing back and forth in the ladder once it touches the table, like an achordeon pulling itself down
@timcameron9023 Says:
nobody cares
@ikartikthakur Says:
it's because of extra pull .. the table one
@Bronyh8r Says:
I theorize as a result of the bars hitting the table, the string that was acting as a rod in free fall has tension relieved. This combined with a shift in the overall ladder’s moment of inertia and the slight torque encountered by the angled bars hitting at different times results in a cg shift downward allowing the ladder to gain momentum and fall faster.
@travislebaube7646 Says:
The rungs act as levers as they hit the table to pull the rest of the ladder down faster.
@zorm_ Says:
Lots of people coming up with the angled explanation but i'm not satisfied. Why would that accelerate the ladder downwards ? It's only pulled by gravity, there is no additional acceleration provided by the ladder pulling itself
I'd be more satisfied by saying that the centers of mass of both ladders are falling at the same speed, which alone would make ladder B much faster than A, but then ladder B is slowed down by hitting the table and stopping on it, slowing it down just enough to appear slightly faster than A
@shizuxo Says:
I wonder why
@steveking7719 Says:
air resistance for ladder A is constant while air resistance for ladder B decreases because the surface area of ladder B is decreasing.
@Eternal_Night69 Says:
Optoon b was slightly ahead since the beginning
@tmaKlopp Says:
Im guessing because there is less mass to accelerate as the one hits the table, so it accelerates faster
@bonemasterj Says:
The one on the right is obviously falling into a black hole and hawking radiation is repelling the one on the left.
@lecoeurdivin7040 Says:
Les échelons déjà posés ne font plus de friction dans l'air, friction qui ralentissait la chute.❤
LATEST COMMENTS