He is so engaged in his explanation about the mechanics of the pendulum, he forgets whish direction the Earth rotates , reminds me of my Professor. I love this channel.

@charismatic1516

4 жыл бұрын

Oh, he has a model @ 0:14 of rotating earth (mag levi) in the background to remind him :-) @ 1:23 Ooops! where did it go?

@ginnyjollykidd

3 жыл бұрын

He got it right, though.

@1977ajax

Жыл бұрын

@@ginnyjollykidd 4:39 Er, no. Watch again and visualize the sun rising in the east. His little globe would have to go the other way for that to happen.

4:49 "And I can't remember which way it [the earth] rotates." The humility of a true scientist!

@MajWinters100

3 жыл бұрын

@Roman M. the whole point of the experiment is showing it DOES rotate lol. And it does. There are hundreds of these pendulums in museums, and it is just as he said.

@MajWinters100

3 жыл бұрын

@Roman M. deaf ears, and blind eyes, I see

@MajWinters100

3 жыл бұрын

@Roman M. true, you're the one calling people idiots first. Thanks for pointing it out.

"That was when I saw the Pendulum. The sphere, hanging from a long wire set into the ceiling of the choir, swayed back and forth with isochronal majesty. I knew -- but anyone could have sensed it in the magic of that serene breathing -- that the period was governed by the square root of the length of the wire and by pi, that number which, however irrational to sublunar minds, through a higher rationality binds the circumference and diameter of all possible circles. The time it took the sphere to swing from end to end was determined by an arcane conspiracy between the most timeless of measures: the singularity of the point of suspension, the duality of the plane's dimensions, the triadic beginning of pi, the secret quadratic nature of the root, and the unnumbered perfection of the circle itself." Rest in peace Umberto Eco.

@UguysRnuts

Жыл бұрын

Heretics

Thank you for making this understandable. I always have difficulty understanding what other people are saying, even if the concept is simple, but I was able to follow you the entire time. You have an excellent way with words!

Love the Foucault pendulum and love the way this professor (most physicists) explain it with body movement. Going as far as showing their backside 01:17 and tickling the North Pole 04:50 Don't know why we do it, but probably is related to our enthousiasm of physics. You may also notice the effect when watching timelaps movies of the interiour of large cathedrals with chandeliers hanging from long suspensions. Although the chandeliers (usually) don't swing you'll see them rotate around their axis until the counter torc of the suspension compensates for the Coriolis force and they jump back to their original orientation. Love physics, and love this channel. Always entertaining and educational!

If the pendulum is attached to a foundation that's attached to the Earth. How is this experiment accurate considering the foundation is attached to the spinning Earth?

@wreckingrich3788

4 күн бұрын

That's the point. If it is not attached than it wouldn't prove anything, would it?

I’m going to build one of these in an old building. It will have a vertical shaft where the line attaches. Once per cycle it will oscillate up and down a small distance, giving it the energy to run continuously, without introducing any lateral error. Also a ball bearing where the line attaches.

@simonneumayr6002

10 ай бұрын

Did you do it?

okay I have an important question here. point at which the pendulum is connected ...is it not rotating along with the earth? did they use some kind of ball bearing or similar so that the plan of pendulum stays constant while the earth rotates? if the pendulum is connected to a ceiling of a building i expect pendulums plane to move along with the rarths rotation since the whole structure/building is moving as well. how did they make pendulum swing independently.

It's also an interesting novel by Umberto Eco.

wow, awesome video. got one at uni and very really understood what it was about... cheers

Excellent explanation. Amazing experiment.

what kind of boggles my mind is that if the pendulum is not suspended in the air (say with a stationary balloon or something) wouldn't the structure its suspended on move with the earth as well cancelling out the effect. It obviously dosent, but.... why not

This is my favorite Professor by far. Always has a witty comment in explanations. Where is he? Hope hes well, would love to hear more from him.

@UguysRnuts

Жыл бұрын

In his own word, "cheeky". A very subtle suggestion that by introducing electromagnetism the museums may be, shall we say, enhancing the spectacle.

Very cool. There is one of these at the Maryland Science Center. I remember it as a child...now I want to go back and see it again, understanding what it actually is.

isn't the support with which pendulum is connected rotating along with the earth? it's really astonishing to observe rotation of earth being in the same frame of reference with the earth itself. thanks to foucault

I like simple experiments that reveal something we can't sense. Nice job :)

We have a big one at the university of Salamanca in Spain

Do a video on the various periods of rotation of the Foucalt pendulum and relate it to conservation of angular momentum. It would be a great video!

That magnetic globe is the coolest lamp in the universe

My physics teacher linked our class here, it's a funny feeling to know your teachers like he same youtubers as you.

What a lovely explanation 😊

Really enjoyed this clip. I am not at all mathematical but this made perfect sense to me. My son would really connect with this. Any tips on setting up a suitable experiment for a nine year old would be appreciated. Well done!

This is some amazing quality content

Very well explained thank you i subscribed

@Jeeve79 The pendulum is not affected by the rotation of the Earth. As shown in the video, the plane of the oscillation of the pendulum is constant and so the pendulum is moving in an inertial reference frame.

Super1Champ The helicopter is still being affected by gravity. So it'll still move with the earth. Just because something is not physically touching the ground doesn't mean it's not affected by the earth's gravity.

I still remember when I first saw this thing vividly in London Scientific museum. I was shocked. We now could think of many crazy ways of demonstrating the Earth's rotation, but who can imagine someone did this long before space age, in such an elegant way? If I saw this when I was much younger and somehow understood it, I would have become a scientist.

I want that globe

@CharlyGK7

7 жыл бұрын

Shahe Ansar have you found out the model or where to buy it? has some one? I want it too heh

@YiannisANO1911

5 жыл бұрын

@@CharlyGK7 did anyone find that globe?

@GEAsolar

4 жыл бұрын

Anyone?

@eltotoX Because the stars experience such a small acceleration as they orbit the galaxy, using them as a reference is a very good approximation to an inertial reference frame (non-accelerating, non-rotating). The stars aren't special, they just make a useful reference. Hope that helps.

For the direction of the tangential velocity you can use a right-hand-grip-rule... if you imagine your thumb is in the same direction as the vector of the connection of the geografical southpole to the geografical northpole your fingers show in the same direction as the tangential velocity of the earth...

Every physicist has their experiment that they get excited about when they hear about it. THIS IS MINE! How simple an experiment can one person do to explain so much. Greatest showcase of science ever.

Thank you for the video.

6:13 - I like the way he's standing

The fact that the pendulum's plane doesn't rotate on the equator and the fact that hurricanes don't form on the equator also seems to support this.

the one at work (radboud university of nijmegen) is driven by a clever magnet setup and during the day you can see the effect which is very cool indeed

so with a pendulum you can measure where north and south, east and west are, cool and also at which latitude you are

this professor is so awesome.

@oisiaa This is Roger Bowley, the professor who does not know which way the world spins. So I screwed up --- it's hard to get everything right when improvising for the camera.

I've just seen this pendulum being demonstrated by James Burke (connections 3). I totally remember learning about it at school but I'd forgotten that the point of it is that that the pendulum is independent to the rotation of the Earth. Amazing! (when I forget which way the Earth rotates I simply remember that the sun rises in the east... so the Earth rotates towards the east... the other way to this video:D)

Good explanation. :)

I think I read Foucault had a magnet under the floor that kept his pendulum going.

In the video there was no mention of the pivot being free to rotate. I'm not sure if it makes a difference in a real situation but wouldn't the pivot rotate with the Earth if it was fixed, in turn making the string rotate. Wouldn't that cause the plane of oscillation to rotate too?

@k39564

Жыл бұрын

Yes. I would think. Wouldn’t The experiment might be more accurate is they place some sort of bearing at the opposite end of the string. This way the string is not bound to rotate with the earth.

4:48 The direction the earth is rotating ... Yes, you can remember. The time zone of New York is about 6h behind London. Keeping that in mind, rotate into the direction where London goes first and New York is behind. Short .. to the east, where the sun comes up in the morning.

Would it be possible to cut down the friction of the air in a vacuum to keep the pendulum moving for a longer period of time?

I would have very much liked this man as my professor.

@mvszao as far as I can tell it uses a 1 magnet in the stand, the top of the globe has some type of metal probably steel or iron and a electric force which i assume flips the fields so quickly that it repels and attracts so that it can not move.

@MrOldprof My deepest apologies sir. I seriously respect your knowledge and absolutely love watching you on Sixty Symbols. It was my error to point out such a simple mistake that anyone could make.

Hey, my college has a huge version of one of these installed our library. Come to think of it, I have no idea if it was put in by the physics department or the psychology department, because only a very small percentage of students (now including myself) know what it is, which makes for a great opportunity to watch confused freshmen question their sanity when they emerge after a long study session to find that the pendulum is moving in a direction completely different from when they came in.

Hello Professor! I love your video's so much, thank you endlessly for sharing your knowledge! I'm hoping to come study at your university soon after doing an access course at college this year. I did a years foundation course for engineering at London South Bank University but didn't finish for health reasons.My question is about the Precession of Earth as discovered by Hipparchus in 130BC and the alignment of Polaris as a marker for our rotational axis.. Apparently this cycle is renewed every 26,000 years. Does this tie into our Julian calendar or even the fact that we measure time from 0AD? Christianity seems to cloud my sensible reasoning, although I do not deny that such events did indeed happen.. To some extent!Thank you very much,Darren Herbert, aspiring student! :)

2 жыл бұрын

Is your dream fulfilled?

Now I believe when Leonard said "I can feel the earth moving!!"

Brilliant!

@Kargoneth Try to imagine it with Vector Forces, If at the poles the Force acts directly perpendicular on the pendulum making it rotate, and at the equator it acts parallel to the pendulum motion, in between both of them, the force should be on an angle which still causes it to rotate around.

When the pendulum is at the equator, would it also be possible for the pendulum to slowly stop oscillating and then be sort of fixed hanging towards the west- because the earth is rotating towards the east Or would it just keep oscillating in the same plane (neglecting any sort of resistance).

As much as I love the quantum mechanics/quantum field theory videos, I still find the classical mechanics videos just as interesting.

@charismatic1516

4 жыл бұрын

Yeeees! Viva, Sir Issac Newton!

The idea that there is a treaty prohibition against trivial and controlled use of flame in a scientific experiment on Antarctica is ridiculous. Any treaty provision against burning on Antarctica would apply to the chronic burning of waste, not prevention of the trivial and controlled use of flame in a scientific experiment. Individual stations on Antarctica would also have strict fire prevention rules, but these would not be codified by treaty; and again, these would not prevent the trivial and controlled use of flame in a scientific experiment.

@TheRhinehart86

9 жыл бұрын

So you're saying that this guy went all the way to Antarctica, spent all day trying to setup the pendulum then gave up in failure because he misinterpreted international treaty? From what I understand lighting a fire in Antarctica is extremely dangerous due to the high wind speeds, low humidity and vast distance from rescue and medical facilities. Also, there ARE treaties dictating fire use, bases have to be constructed in certain ways and certain distances from one another to prevent them setting each other on fire. In addition there are several facilities and instruments at the geographic south pole, several countries would be quite upset if you burned them all down doing an experiment.

@sinephase

9 жыл бұрын

dlwatib Antarctica is one interesting place, just as much for its international relations uniqueness as well as its physical details. :)

@rcook2608

6 жыл бұрын

TheRhinehart86 LOL yeah, real dangerous to start a fire outside in a barren ice swept wasteland, devoid of any vegetation.

@pansepot1490

5 жыл бұрын

Yup. Water ice is notorious for its high flammability.

@massimookissed1023

5 жыл бұрын

Never mind the gallons of petrol they burned just driving there.

but does the roation or earth first rotate the string and then this string rotation is moved to the pendulum at the bottom and that is the whole causal link that changes the orientation of the pendulum ? nobody doesn't explain that if you have something on the string hanging then when you rotate the string it will rotate back to it's "zero" position.

@carlsontechnology I would say it depends on the toilet not on which hemisphere it's located. A toilet wouldn't swirl at all if it wasn't designed to.

Loved it ...

"Excuse me Brady I am showing my backside" XDDDDDDDDDDDDDDDDDDDDDDDDDDDDD

@Kevin-sy8uf

3 жыл бұрын

this is the kind of professor who made college one of the best experiences in my life

Maybe the apparent motion of the swinging pendulum does not change, it stays the same, but the earth is moving under it, giving the impression that the pendulum is exhibiting precessinon.

@kknd-krossfire1114

7 жыл бұрын

Jack Gamboa That's what he's talking about

@ct8618

7 жыл бұрын

Maybe? Uh dude were you paying attention to the video or what? Haha

No, When you turn off an a electromagnet the ball will still remain magnetized for a short time and unevenly release from the magnet. sort of like a "stickiness". this would interfere with the initial swing of the ball.

Clever man. I thought he may know by now which way the earth rotates

Ha I've seen this before, never knew what it was called or who was behind it!

So, how long does a pendulum take to loose all of it's energy? Is there an easy (or hard) way to calculate that? I imagine that a couple coefficients of fricative force apply, but please enlighten me.

It would swing for much longer but it still loses energy in the bending of the string! I wonder if you could measure how much energy it takes to bend a string on each swing of the pendulum.

But the support for the pendulum is also rotating....so its the relative rotation that the pendulul swing captures ? or please clarify even at the North and South Pole the Pendulum is attached to the earth and is not floating in space

I really could listen to Professor Bowley speak all day long.

I can visualise why it works at the Poles and not at the Equator but for all the middle latitudes all I can do is a mathematical interpolation. I've never really managed a proper mental image of what is happening. In a similar but different kind of way, this reminds me of the Coriolis effect.

We should add that at South Pole, the idea the pendulum is moving in the opposite direction when compared to the northern hemisphere, is only a matter of orientation. The earth rotates the same way at both poles - face North and the pendulum swings like it does up north.

@sissyfus6181

3 ай бұрын

The pendulum precesses clockwise in northern hemisphere and counter clockwise in southern hemisphere. Also it precesses as a function of its latitude. 24 hours for 360 degreees of precession at both poles, and zero at the equator.

@MariaMartinez-researcher

3 ай бұрын

When you are in the South Pole, every direction you face is North.

Thinking back to prof B on a swing moving his weight up and down (nearer and further from the fulcrum), couldn' t you put a battery powered device on the big weight which moves a smaller weight in this way? Could keep going until the battery is flat. Not as elegant as the original, though.

Philadelphia's Franklin Institute Science Museum put their Foucault Pendulum in the basemen of a large staircase so visitors pass it several times during a visit. There were plaques set up at each floor to explain it. When I worked there 35 years ago I would start the day setting up the brass pins around the base and start the pendulum swinging. They've since remodelled it. The pins are in a much smaller circle and there's some sort of moving globe in the centre. It spoils the simplicity of it.

Very true, however I said "you can't LIGHT a flame" not IGNITE. I believe that a hypergolic propellant engine would produce to much vibration interference on the pendulum and would also allow more gas into the vacuum making all our efforts moot. I think what would work better would be a steel string with a small fuse wire connecting it to the pendulum. we then run an electric current, the fuse breaks and the pendulum swings.

I'm pretty sure the earth rotates the other way

@ulfhenarpolymathmilitant6258

6 жыл бұрын

it does..........and he's a scientist ? ppppffffhhhhhttttt WETF

@warp65

6 жыл бұрын

Chris Jones You are correct

@SpecialKapson

6 жыл бұрын

He pointed out he might be wrong

@redpillrat163

5 жыл бұрын

The earth does not rotate, it is immovable.

@desmega7693

5 жыл бұрын

Pretty sure the earth doesn't even rotate. LOL!

The plane in which it swings remains unchanged. So if you drew a line over which the pendulum swings, 12 hours later it will still follow that line.

I've just searched through the full text of the antarctic treaty and I can't find any reference to the prohibition of open flames. I have read Allan Baker's website about the experience/experiment and he does indeed state that it is against the treaty. Anyone have anymore information about this? Seems strange to forbid the use of fire in this manner when the second article of the treaty supports 'freedom of scientific investigation'. That is all.

So interesting!

@rjhrjh3 Toilets are designed with the intention of water too rotate, not just enter straight down into the center of the bowl. The nozzles are angled.

can you make it in a vaccum chamber? Remove the air resistance, will it make go for 24 hours?

@RSP13

9 жыл бұрын

You probably would also have to mitigate the fact that the wire presents a small torsional resistance. If the planet twists the wire, the wire will twist the ball and everything will be kept together. You could put a magnetic joint on top, though.

@ferrumignis

5 жыл бұрын

@@RSP13 Also hysteretic losses in the wire. Should be possible though, but would need a large vacuum chamber and it's one of those pointless experiments that only flat earthers demand, and they still wouldn't be satisfied with the outcome.

A fixed location time lapse of nighttime stars gives a similar feeling.

Thank you sir

If you would put the pendulum in a void it would increase the period in which observation could be done.

If the suspension point of the pendulum is fixed, doesn't it acquire a torque as the Earth rotates, or is it the torque that causes the pendulum to change the direction of its swing? What if it was suspended on a frictionless, torqueless mount?

@sissyfus6181

Ай бұрын

You answered yourself in the last part of your comment. At least as "frictionless" as can be.

@physicsbugga wind is a factor to include on this myth something of larger scale like a hurricane vortex do they form in different direction depending side of equator they begin ?

when the earth rotates, does air rotate with it? I have seen little toys and such (kind of like the globe in the video) that can levitate, if someone was to up a mark on the levitating toy, after 24 hours would the mark be pointing in a different direction?

Can I ask where the levitating globe was bought? @sixtysymbols

just asking but would it go clockwise or anti clockwise?

Take something with some length and a bit of weight on the end, maybe like a teabag, or tea infuser, or maybe a pair of headphones with some extra weight at the end or something, and hold your hand out with the end of the string being held by it. Lift the weighted end so it is taught and at an angle where it will swing for a while. Let it go. Walk in a circle, with the focal point of the pendulum as close to the middle as possible. It swings back and forth in the same plane the whole time.

Awesome video. I was interested in the last point though (the relationship of the plane of oscillation with respect to Sun and distant stars etc). I watched that segment (towards the end) again and still am not sure what exactly is the conclusion. Is the plane actually constant with respect to the distant stars, or not?

@SoundbytesMusic

6 жыл бұрын

I would assume that earth rotation around the sun does not effect the pendulums plane of oscillation. Our daily rotation is a spin effect while the annual rotation is caused by gravity.

Keywords: "THE TRICK IS..."

The big church in our city also has this demonstration. Pretty cool actually.

This was infinitely better than Sci Show's explanation.

Nice. =) I imagine one could do the same thing with a gyroscope. Probably easier to keep in motion than a pendulum would be too.

@mrblisterfist counterclockwise is used for 2D but what's used for 3D? if the earth rotates counterclockwise from the north pole, it is the opposite direction from the south pole.

Does the toilet swirl opposite in the northern and souther hemisphere?

Whoooaaa, that's a very cool globe! Where can I get one?

It's odd how motion is relative, but something about rotation is more absolute. Haven't gotten my head around that yet...

if they made the pendulum outof a denser material (ie: depleted uranium), it would have less air-drag and would swing for longer. Is it possible to design a more aerodynamic pendulum? perhaps a disc instead of a sphere.

He and Ed Copeland are my favs:)

And if you just think a little about it, you'd see you already answered your own question: At equator it does not rotate, and at the poles it rotates in 24 hours: Therefore if you see a rotation of 40 hours, you can work out your latitude. If I had 3 measurements, I could work out the equation.

@8DX As well as obvious gravity but wind / pressure is a factor on the pool of water surface weather it is high or low i think it is part of coriolis effect isnt it ! quaternion