Prof. Kathryn Mayer show's us how to suspend a water bottle with just some string and a few matches. See more stupid physics tricks here: • Stupid Physics Tricks
Пікірлер: 38
@dannydiaz56753 жыл бұрын
I love how she explains it! Gonna try to do it tomorrow! Thanks for the video!
@dannydiaz56753 жыл бұрын
IT WORKS!!!! At first try I failed, but then it worked perfectly, and we were all amazed XD
@heroichitsuji3 жыл бұрын
Me: Looking for an explanation The physicists: Well we’re physicists so we have to free body diagram it me: YES!
@baraskparas95592 жыл бұрын
Magnificent demo.
@nizammahazir70272 жыл бұрын
Still didnt understand
@joeimaverage44242 ай бұрын
Cancel gravity, Awesome.
@SR-bu6kz6 ай бұрын
What about the component horizontal force from the diagonal matchstick?
@ChaseR28_ Жыл бұрын
The FBD has bothered me for a really long time now. The no torque from the tension is fine, but that should be the end of the story. The normal force shown can't exist because the matchstick isn't lying flat; it rotates ever so slightly, maybe only two or three degrees. But if it did lie flat, the diagonal matchstick's force still wouldn't make sense. It's implied the force comes from compression against the first match but the compression has an equal and opposite force into that first match as well. It can't push on anything.
@bababoi9078 Жыл бұрын
This is because the bottles weight is distributed on two separate points. But not evenly
@bababoi9078 Жыл бұрын
Okay ive been thinking about this question. Its bugging me alot.
@realistic_holder1571 Жыл бұрын
The FBD is is wrong. what really happens is that the centre of mass of the bottle is pushed by the slanted match slightly backwards behind the edge of the table.
@mln-mal Жыл бұрын
She is a very nice teacher
@dandooni13263 жыл бұрын
How will a measure of a turning force hold a mass?
@ankk986 ай бұрын
mind blown
@M_M_Dz6 ай бұрын
That's because the net torque is 0 by the additional matches sticks
@Naked_Snake3 жыл бұрын
At 3:20 you say the tension is at the pivot point, but really the string is ever so slightly in front of the table. How does it still not tip considering this fact? Is it because of friction?
@Prof-Hafner2 жыл бұрын
Yes so really the string is applying a bit of clockwise torque (along with the table). So that just means the diagonal matchstick has to apply even more the other way (counterclockwise). It can do this because the static friction force between the top match and the table that it is pushing against can take a variable value, up to the maximum mu*N, if you know what I mean. If the coefficient of friction is too low, the diagonal matchstick will make the top one slide and it won't work.
@Naked_Snake2 жыл бұрын
@@Prof-Hafner That makes sense, thanks!
@origionalcatastrophe6 ай бұрын
That is the incorrect explanation. It needs to stated the bottle is creating a down force but that force is countered by the vertical match being held by the match splitting the string.
@DoppaD Жыл бұрын
The trippiest part was the glitching from 2:30 to 2:33
@Prof-Hafner Жыл бұрын
One of us miss spoke and it was cause lots of confusion so I headed it out.
@arpitchaudhary5524 Жыл бұрын
Maam, what is role of centre of gravity in the above experiment video?
@Prof-Hafner Жыл бұрын
In general, when something hangs in a stable configuration, the center of mass must be directly below the pivot point that the object hangs from since this configuration will result in zero net torque.
@arpitchaudhary5524 Жыл бұрын
Thank you maam
@ricardoabh32423 жыл бұрын
The diagonal match must be equal or greater in length?
@Prof-Hafner3 жыл бұрын
The matches were all the same. Dr. Mayer is the expert, but I think how long the diagonal match needs to be just depends on what angle in the strings is set by the first match.
@chrisreyes81822 жыл бұрын
If you have a time machine and go back through time like roman empire time or pompiie is about to go boom boom and show this trick ha your head might end up ina bucket or burn you alive and acuse you for witch craft 😆
@Prof-Hafner2 жыл бұрын
I'd take that over living without indoor plumbing! :)
@chrisreyes81822 жыл бұрын
@@Prof-Hafner dont worry my old friend il protect at all cost 😅 would you show this explaination to leonardo if ever we can go back or he probly knows this?
@jayeisenhardt13372 жыл бұрын
@@Prof-Hafner Isn't the Roman Empire what made indoor plumbing a thing?
@Taricus2 жыл бұрын
@@jayeisenhardt1337 lol they did have indoor plumbing :P That's what the aquaducts were for. It used physics to create the water pressure, by taking the water from somewhere high and using raised platforms to keep it high above the ground before reaching the city (just like how we use water towers). Gravity makes it work without electricity or pumps.
@user-qe7if4gk4c2 жыл бұрын
มาจากไทยนะคับ55
@Prof-Hafner2 жыл бұрын
Welcome!
@Tecnotronics2232 жыл бұрын
All what she said its an explanation by mind.... But before this experiment.. She didn't create this Experiment ....by the same logic... This only explanation.... But explanation can't creat facts
@thewanderer12464 ай бұрын
Aint this fake
@Prof-Hafner4 ай бұрын
No. And if you don’t believe me there are about 10,000 YT videos on it by now. 😂
@jjborenfff Жыл бұрын
What's stupid about this?
@Prof-Hafner Жыл бұрын
Actually I agree that one is not so stupid. But if you peruse the entire playlist, I think you will find that many of them are: kzbin.info/aero/PL9_sR6QqqcymqSt5BuprSZLeDjdsNpHAH