Know your magnets polarities
ฝัง
- เผยแพร่เมื่อ 22 ก.ค. 2024
- This video is part of a little series of videos I'm making on handling neodymium magnets safely. In this video I will show you how to determine the poles on disc, cube and sphere magnets. Knowing your magnets polarity is very useful for safely combining large magnets as shown in one of my other videos in this series.
Music is by Kevin MacLeod (from his website incompetech.com) and Nick van Man (from his website music4yourvids.co.uk) used under Creative Commons license. Tracks used:
0:00 - 0:06 'Supernatural' by Kevin MacLeod
ISRC: USUAN1100397
0:06 - 5:40 'Watching the sun go down' by Rick Van Man
Here are the captions in case you don't understand my Danish accent:
- Hi. In an earlier video I showed the advantages of knowing the polarities of your magnets. In this video I'm gonna show you how to determine the polarities of your magnets. Where is the north pole?
- The professional way is to buy a dedicated pole detector. With just a click on a button it will tell you whether it's a north pole or a south pole you are pointing towards.
- This is my favorite method. Use an old-school compass.
- Let's start with a disc magnet as these are the easiest to determine. The poles are on the large flat surfaces. I let the magnet stand on its side so the poles are pointing towards the compass. Now I spin the magnet until the south part of the compass needle - which is actually a small magnet in itself - points towards the disc magnet.
- With magnets opposite polarities attracts so now I know the north pole of my disc magnet is pointing towards the compass. I mark the north pole of the magnet with an N. And double check just for good measure. If I spin the magnet with no poles pointing towards the compass the needle doesn't move. This is valuable information for our next challenge: The cube magnet.
- On a cube magnet you can't tell by the naked eye on which two surfaces the poles are. So you just have to put it randomly down. In this case I was a little unlucky and put the magnet down with its sides pointing towards the compass. Because the compass needle is not spinning along with the magnet. Therefore the poles of the magnet must be on the top and bottom surfaces and I have to tilt the magnet 90 degrees. Now the poles are pointing towards the compass and I do exactly the same as with the disc magnet.
- With south pointing towards the magnet I have found the north pole of my magnet. Right here. I mark the north pole of the magnet with an N.
- And now for the real challenge: The sphere magnet. Where are the poles on this one?
- With a magnet that can roll in all directions it is very hard to get a steady and exact reading. The solution is to put the magnet on what I call a security board. This is just a thin wooden plate with a metal plate glued to the backside. On this board the magnet will always align with one pole pointing directly into the board and the other pole pointing directly upwards.
- By now you should have figured out how to find the north pole.
- The final method I am going to show you is to use the magnet as a compass in itself. In this case I'm going to use two small magnets from a play set. By hanging them on a long tension-free line the magnets will act as a compass and align with the Earth's magnetic field. I cannot force them to point in another direction. Eventually they will stop pointing in the same direction everytime. Make sure there is not metal close by - just like when you use a compass.
- Here I point towards the geographic north. By definition the north pole of a magnet is the pole pointing towards the geographic north so northpole on a magnet is short for northpointing pole. That means I can mark the pole pointing towards north as the north pole.
- Another version of this method is to float the magnet on some styrofoam in the middle of a waterbath. It takes a little more preparation but has much faster response time as shown.
- Once you have determined the polarities of one magnet you can use it to determine it on all other magnets. The south pole of the marked magnet will stick to the north pole of your unmarked magnet. - วิทยาศาสตร์และเทคโนโลยี
FINALLY!! Someone who can explain and show us how to find the North side of a magnet. I have been so confused about this topic and the way that you showed how it works was so helpful. Thanks so much.
Really....
🙏 the session-part where you use the compass are the most important for me… thank you! Learning all the time I am ☺️
Excellent tutorial on finding North and South poles of a magnet. Well done!
Backwards...
Thank you for publishing this highly useful tutorial. You inspired me to purchase an orienteering compass I fully intend to use on my next camping adventure. But for now, I really need this compass so I may mark the N & S poles of these expensive Neodymium cube magnets I recently purchased. You rock!
compasses point to the
south pole
of a magnet. This is because compasses are made to point to magnetic south, and the
geographic North Pole

coincides with the
south magnetic pole

of the Earth.
The north end of a magnet in a compass is attracted to the south magnetic pole, which lies close to the geographic north pole.
s
Excellent tutorial on finding North and South poles of a magnet. I have spent hours trying to get alternator to work with out knowing which way the permanent mags are pointing.
Well done!
Pleasant music and voice! Thanks! I like method 3 as it is the most basic, fundamental and origin.
Thanks for posting. I have magnets of different shapes and had fun with the compass.
@IroniMan100 :
Thanks for watching and subscribing! I will make more magnet videos - maybe not soon but they will come :o)
The convention in early compasses was to call the end of the needle pointing to the Earth's North Magnetic Pole the "north pole" (or "north-seeking pole") and the other end the "south pole" (the names are often abbreviated to "N" and "S"). Because opposite poles attract, this definition means that the Earth's North Magnetic Pole is actually a magnetic south pole and the Earth's South Magnetic Pole is a magnetic north pole.[5][6] The direction of magnetic field lines are defined to emerge from the magnet's north pole and enter the magnet's south pole.
Peanut! You are absolutely correct and luckily l read your comment and it saved me from writing virtually the same factual information. It certainly is refreshing to see others who have a knowledge that is greater than most on a subject that everyone should be aware of with a superior understanding and knowledge of.
this looks copied from Wikipedia
Thank you Peanut! You too steve russell:)
Thank you for watching and commenting :)
You're right. Nature doesn't care about north/south. It's a convention that we humans have decided to apply to nature. And by our definition the pole on a loose magnet pointing close to the geographic north is the north pole on the magnet. Therefore the magnetic pole of the Earth near the geographic north pole is the magnetic south pole of the Earth. That's rather confusing and I didn't want to include it in the video :)
You comment that the north and south poles are conventional we humans have decided north and south pole. But I have learned that the magnetic lines of force goes from north to south outside magnet and south to north inside the magnet. Is this also conventional. And can we determine polarity of magnet without using any reference. Thanks for your explantion.
Very informative! Thank you for the lesson.
Wow the best video...... thanks for sharing. FINALLY!! Someone who can explain and show us how to find the North side of a magnet
Exactly what I needed, great tut. thanks.
Thanks! This video was very helpful and easy to understand.
This is amazing!
Thank you so much for this video ‼️👍🏼😀
Because opposite polarity attracts (1:07) which means that the north earth magnetic field which the north needle of the magnetic compass points is actually south because the surface of your magnet which you marked as "N" (north) is attracted to the south portion of the magnetic compass (1:16).
Your presentation is nicely done. Your Danish accent is great. Thank you
Charles Bonnici Thanks for watching and commenting :)
It is something that we humans have decided to have a common standard. Nature doesn't know of north and south - it's just our convention :)
Thanks for watching and commenting!
Very informative. Thank you.
you saved me a headache trying to figure out the North Pole. Thanks!!
Best! I'm starting to love and want magnets!!
Thanks - more videos with magnets coming up :)
I don't have magnets from CD and DVD units but I guess they are similar to the ones in hard disk drives that I have quite a lot of. These are multipole magnets and have both a north and south pole on each flat surface (4 poles). I think they magnetize them in this way to keep the magnetic field very close to the magnet so it doesn't erase the info on the HDD-platters :)
So yes - it is possible to have both a south and north pole on the same surface.
It's interesting how the South Pole of the planet is actually the magnetic North Pole.
Or is the compass marked wrong...?
If the compass is marked wrong then that's the South Pole of your magnet.
If what we call the South Pole is actually the magnetic North Pole of the planet then that's just shenanigans.
Very nice, very helpful
very clear ... excellent !!
Nice idea about the sphere
Thanks, this was really helpful!
And I really like magnetism :)
Very educational thanks
Thanks Brainiac75.Awesome video.
Awesome Videos!
Edu.Science Thank you for watching :)
*Thank you so much* 👍👍👍
wow. thanq for sharing the video.
Well done!
Thanks for watching :)
Helpful. Thank You..
very informative info..thanks very muchly :)
Your content is really interesting. Your voice is also very soothing, as are your background music choices.
Thanks :) Much more to come in the same style.
Great video
Saved me life
I have lodestone sphere magnets after using them for quite some time now I have seen were the poles are but couldn't figure out which pole was which
Since the earths geographic north is magnetically south, do you happen to know which description is used when someone describes the polls of a magnet?
Thanks!
3:40
Geomag! I love that stuff!
Happy Christmas Brian
Nice!
Glad that I could help! The topic can be very confusing (just look at some of the other comments to this video...)
Actually, the geographical north-pole correspond to the magnetic south-pole of the earth. So the "north" needle on the compass is pointing to the right direction (the geographical north) just because opposite poles attracts each other.
well explained
When hanging the magnets by the string, how could you tell the magnets were attracting to the north section. Basically how could you tell the proper direction?
Thank you
Is it possible to have a north pole at the center of a circular plate magnet?
You should've added that the magnetic north pole is actually located in the geographic south pole and vice versa. It's just another way of saying it but that part at 4:10 got me a little confused lol (maybe it's just me tho). in any case, great vid!
I have never even touched a magnet but still your vids are interesting.
good video
Good vid herr braniac.
thank you sooo much
Nice job as always! The compass method is twisting my head. The white part of the compass needle points towards the south pole so you would think there is a northpole magnet at the end of it because opposites attract, right? But what you are actually saying is that the compass needles southpole magnet is pointing towards southpole. I don't get this, what am I missing here? I tried the floating magnet method and I came to the same conclusion: the northpole of the magnet is pointing towards north? Also we did a interesting magnetic experiment on 2 different hemispheres where I stumbled into this same phenomena. Is it just that the pole on the northern hemisphere what we call north pole is actually magnetic south? Please enlighten me.
+Cobrakiller2000
You have figured it out yourself: the magnetic south pole of Earth is located near the geographical north pole. When the north pole of a magnet points in the direction of geographical north it is because the magnetic south pole is located up there - opposites attract :)
Thanks for watching.
+Cobrakiller2000 The Geographical north pole is actually a magnetic south pole, therefore the Northern arm on a compass will be attracted to geographical north.....not due to the polarity of the compass itself but rather the difference in geographical north actually being the magnetic south. I said it twice but meh :P
Lucas McNea
Yes I figured it out eventually. needlessly confusing. Somebody in a survival situation trying to figure out compass points with a magnet could end up going to the wrong direction without this knowledge :)
Its because the pole of a magnet was named after the direction of attraction, before magnets were really understood. Now, try learning about electrical polarity and electron flow vs conventional current LOL.
Hey cud you tell me the size and grade of this sphere ? Im looking for a 1.5 n45 or n42 would this be able to be found,?
This is very good. Thanks. I have a question, though. I'm searching for which side of a magnet is north and which is south. I have come upon answers that say the north of a magnet points south (some of these sources are authoritative-looking) instead of pointing north. If you know why there are opposing opinions will you please tell me? I'm confused at this point. Thanks.
Got a question: I am trying to construct an invention with the use of magnets and I was told I could kill the magnetic charge by running a currant through it.
How do I do that?
Thanks for this. I followed your instructions for the magnets but it is not clear to me which way you point the magnets. Is north south aligned to the flow? or south/north axis aligned to direction of flow? great work!
I have problem, I can't direction the north in my room, its give me different north !
@LJnandSrada :
By definition the northpole of a magnet is the pole of the magnet that points towards the geographic north.
The reason for confusion could be that the Earth is a magnet in itself (thats why compasses work). And the Earth's magnetic southpole must be at the geographic northpole since our magnets point the northpole at the geographic northpole which is magnetic southpole...
Confusing yes, but a loose magnet will point its northpole against north. That's all you need to know.
When the compass is pointing north the side facing the compass south?
That could work but as you point out in your comment it is easy to get north and south mixed up on an electromagnet. The north pole of the electromagnet is determined by using your right hand. Wrap your fingers around the coil in the same direction as the current is flowing (the 'conventional current flow' from + to -). The direction your thumb is pointing is the direction of the magnetic field, so north would come out of the electromagnet in the direction of your thumb.
Could you explain that magnetic north pole of compass show magnetic south pole of the Earth wich is at the geographic north of the Earth ?
thank you
Thanks! I always wondered because I have cylinder magnets
So, I'm still a little confused. If I wrap a wire around a nail so that it resembles a regular screw💈. If I attach the top wire to the positive end of battery which end would be north, top or bottom?
Excellent videos (all of them!) The Earth is a giant magnet. The North-seeking Pole of any magnet appears to "seek" Geographic North, but is actually attracted to Magnetic South, which is near the Earth's Geographic North Pole. Likewise, the Earth's Magnetic North Pole is near the Geographic South Pole.
So how do you know that south of Earth magnet is on the geographic north? Is that just an agreement or is any scientific explanation behind? Thanks for your answer.
Thanks for this great demo. I was pointing my disc magnets incorrectly to relieve my toe arthritis pain, they need to have north facing the body, your video allowed me to measure them correctly.
can you do a video explaining the shapes of the magnetic fields from differently shaped magnets?
Magnets are either Axially Magnetized (would be the small distance on a cylinder magnet measuring 1/2" x 2") or Diametrically Magnetized (would be the long distance on a cylinder magnet measuring 1/2" x 2").
I am so relieved that so many others were experiencing the same confusion as me. My first question was, on the compass needle, does the needle contain a magnet, with the south pole magnet on the "red" north end, and the north polarity magnet on the south (white) end???This would clarify everything. If I dont get a reply soon, I will just deconstruct my daughters cheap compass to find out! :) Ken Byrd
boatbyrd: Yes you're correct......the South pole of the needle (usually red or orange) is attracted to the North pole of the earth because opposites attract.
Hey dude! All your videos are amazing... specially those about magnets =D. I've got a question... I have some little magnets that i got from cd and dvd pc units. They are tiny and rectangular (10x6.5x2 mm) but they seems to have no poles x_x they shows no repulsion in any face. I attached one on a cork and floated it to do some tests with another magnet and they appear to have different poles on each corner... is this even possible? do you know something about this??
Ty
Can anyone explain ...why torroid do not have poles whereas the circular hollow magnets have poles?
What is the dimension of the disc magnet?
I love your magnet videos. Thanks for making them.
If I understood correctly, you said that the pole of a magnet that is attracted to Earth north is marked North. Since opposite poles attract that means that the Earth north pole is actually South. Right?
I think I've heard this before and I see why that convention is followed, it's just a bit confusing to think about.
Humans created direction before they knew about magnetism. Scientists are very reluctant to change information they have spent their lives on. Cosmologist are the worst.
What is the size and grade of the cube?
Interesting, could the cube have 3 potential north south manetic axis? Will the compass react if the magnet cube is on the table is diametrically oriented to the compass? Also hanging a magnet will orient to a north south axis of course but maybe not which is which without looking at the sun? I am not trying to nit-pick your video, these are serious questions with the utmost respect to you and your channel.
Thank you O:)
Please could you do a video for me? I don't understand the energy of magnets - where does this quite substantial energy come from and why has it not been able to create a perpetual motion machine? Sorry if this sounds simplistic, I am very curious though.
Ken wheeler at youtube channel Theoria Apophasis has a series of magnetism videos that go into great detail. Start with video 9 in the series.
how do they work?!?!?!
But if you don't know which way is north, and you don't know which end of magnet is north, could you possibly head south accidently if all you have is a magnet to point?
@brainiac75
Thanks for answering.
If I view the earth as a giant magnet, knowing that the northpole of a magnet is attracted to the southpole of another magnet, what you say makes perfect sense to me Thanks, again.
I am confused. Aren't the hands of the compass opposite from the poles it attracts (e.g., the North Red hand has a polarity of the south while the South white hand has a polarity of the north)? Doesn't this mean that the side of the magnet that attracts the South White hand is actually south?
Thanks!
Yes, but I didn't want to overcomplicate this video.
Unless you live very close to or between the magnetic and geographic north pole it makes no difference at all :)
I am a bit confused, I remember from science class that opposites attract and like poles repel, so is the North pointing red indicator on the compass magnetized as a South pole or is the North pole of Earth really the South pole?
+Mark Paul Jordan They'll tell you that the earth's north pole is actually the magnetic south pole, but these guys claim that is wrong; The end of your compass needle that is pointing to the geographic north pole is actually the south pole of the needle. I don't really know who to believe, but I own one of these biomagnets and the one thing I can say is that you do feel a difference in the effects of each pole.
www.magnetage.com/FAQ.html#What_are_the_the_two_different_effects_of_the_North_and_South_poles,_first_discovered_by_Davis_and_Rawls
+Mark Paul Jordan the geographic north pole is a magnetic south pole
***** Actually that's wrong (contrary to what orthodox science claims)… Look up the biomagnet research of Rawls & Davis, they state that it's the SOUTH POLE of a compass that points to magnetic north, and claim that the spin of the magnetic fields confirms that the magnetic north pole of the earth is near the geographic north pole.
+Remixomitosis
Well, that's actually a quite useless debate of semantics. Nature doesn't know of north and south. That's just a label that we humans have given the poles.
+Brainiac75 Yes and no. The names themselves are merely for the sake of convention, but my emphasis is necessary for the sake of consistency: The directions of magnetic spin are demonstrably different, so its absolutely wrong to state that the "north pole" of a compass points north. It shouls either be referred to as a south pole or a north-seeking pole. You could just as easily do away with semantic and say that nature doesnt have a north ans south, or any other cardinal direction... but your statement would be the pointless one, because these relative terms have an extremely practical use and we need them.
If the magnet attracts the north, wouldn't that be the south pole of the magnet attracting it & the north pole of the magnet would repel the north pole of the earth?
lol u are superb!
Soo the vacuum is a north pole and the force is the south pole... Any idea pls...
You shouldn't wrap your fingers in the direction of the winding. You should wrap your fingers in the direction that the current flows in the windings. Therefore a polarity change will also change how you hold your hand and which way your thumb points.
So the poles do switch side when the polarity is switched and the rule of thumb works :)
Hello, You seem like a magnet expert. I have a question. I found out that there is an easy way to determine polarities of a magnet only with a needle and a thread. Please correct me I am wrong! So if I lay a magnet on a table with pole facing up and If I hold a needle in a thread hanging from obove towards the magnet it will be strongly atrrackt on one side of the magnet and it would be strongly repel the needle on the other side. So strongly that the tip of needle would be pointing up. So which side is which side of the magnet then?? Hope you can help. Greetings from Norway;)
+MissGreyBlueEyes
Hi, you can't determine the polarities of a magnet that way, unless you know the polarities of the needle.
The needle is magnetized by the magnet and therefore acts as a magnet in itself. But since you don't know the poles of the magnet or the needle, you can't tell north from south poles on either.
If the needle is heavily magnetized you may be able to suspend it horizontally on the middle in a thread - away from the magnet - and let the needle act like a compass needle. One point of the needle should point towards the geographic north pole. This is the magnetic north pole of the needle which is repelled by the north pole on the magnet and attracted towards the south pole of the magnet. But don't let the needle get to close to the magnet. It may just remagnetize the needle and reverse the poles giving you false readings :) Hope it makes sense and helps you.
+Brainiac75 thank you, it totaly makes sence. But can you explane why North side of a magnet is called negative side??
MissGreyBlueEyes No? Positive and negative is used to describe an electric charge. Magnetism is (always) described with north/south pole.
According to what are you define north and south? If north of earth magnet on north side, then your red part of compas needle is south pole of magnet. In this video is just oposite???
I was thinking the same thing. 😆
No
Wow ;)
aún me acuerdo cuando me compré mi caja de magnetix o algo así se llamaban
My sphere is an 1 inch N45. I live in Europe (Denmark) and don't know much about the American market but magnet4less ( .) com has an 1.5 inch N42 sphere for $37.
Is there availability of small spheres and big spheres compared to 1 inch size?
So it's opposites attracts?...when our north poles(mark red) on our compass points N....that's really South pole of planet Earth....because opposites attracts! so the North pole is really the South pole and the South pole is really the North pole?
Close, just backwards though. The red end that points to the Earth's north pole is actually the south pole of the magnet.
.
oh ok...than why are schools teaching kids that the red part is north side of the magnet?? or is that just a big misconception?
Probably a misconception on most people's part..and it's probably easier to remember which way is North that way Heck almost everything you learn in on level of school you find out was not quite right, or flat out wrong in the on the next level.
yeah totally....thanks for the insight.
Henry Sutton At 4:10 of the video he shows that the North pole of his magnet is pointing to the North pole of the earth and he then marks his magnet with a pen showing that his magnet's North pole is the one pointing geographically North.
Is this opposite of what you are saying or am I misunderstanding?
thank you for your health bro
whats the difference between neo and ferrite?
Neodymium magnets are a more modern type of magnet and actually the strongest known permanent magnetic material. A neo magnet is at least 10 times stronger than a ferrite magnet of the same size.
The neodymium is however an expensive element so neos also cost a lot more...
Also, Neodymium magnets are like ceramic in the inside and can break very easily, while ferrite magnets are usually much more resistant to impact.