All Questions
Tagged with magnet electromagnetism
37 questions
1
vote
1
answer
79
views
Core memory output line question
How is a bit read from the core memory pictured below? I understand current through 1 and 1 vs 0 and 0 will change the torus magnets field setting a bit. I’m confused how this field is read back using ...
3
votes
3
answers
251
views
Deflection of current in a metal plate conductor
If I have a metal plate (square in shape) and an electric current moves from one side to the other. I understand that most of the current will take the path of least resistance but all paths will be ...
0
votes
1
answer
49
views
If I have two magnets repelling each other, will they always form a peak in the middle?
If I have two identical magnets, aligned so they repel each other a distance of X apart and at a height of Z I have Hall effect sensor, the peak of the magnetic field sensed will be at the distance X/...
0
votes
1
answer
51
views
Where does the electricity in electromagnets come from if permanent magnets from generators decrease their magnetic strength?
The question has been puzzling me for some time, I presume electrical power starts from generators, the heat produced by them(generators) cause their magnets to weaken and electromagnets have to be ...
0
votes
2
answers
136
views
Re-Magnetizing A Magna-Tip Screwdriver Handle
See what I added to the bottom of this question
Sorry for the high school level question. I would rather not spend my time experimenting. I have a quality gunsmith screwdriver set. The set contains ...
-1
votes
1
answer
83
views
Would a electromagnet be used to detect the presence of a permanent magnet?
I was wondering if there is any way I could use an electromagnet to detect the presence of a permanent magnet.
I am specifically thinking of using a planar type small coil. Maybe use a core or ...
1
vote
2
answers
246
views
Electromagnet design and powering it up? (Fault prevention of DC supply for a small coiled Electromagnet)
I want to create an array of multiple electromagnet which I will be controlling using a microcontroller.
I will have around 100 such magnets lined in a squared grid 10x10. Only three or five at a time ...
0
votes
0
answers
64
views
Making an automated chessboard [duplicate]
I want to create an automated chessboard. At the moment, I'm making the project and deciding what technology to use to detect which piece is at what position and how to move them. I'm not so skilled ...
0
votes
0
answers
88
views
Calculating optimum shape of an air core solenoid magnet pair with given number of turns
Consider a cylindrical \$N52\$ magnet with mass \$m_0\$ travelling in horizontal x-axis with initial velocity \$v_0\$ in \$-x\$ to \$+x\$ direction. It passes through an copper air core solenoid on ...
1
vote
2
answers
322
views
Can a weak external magnetic field damage a magnetron?
I have a 40-year old microwave oven. I temporarily attached a magnetic flashlight to the side of it. Its 5/8"-diameter magnet is likely a neodymium magnet, strong enough to secure the 10-ounce ...
0
votes
1
answer
318
views
NFC and magnet interference in a concrete piece
Do you know if both NFC and a magnet would work correctly in this scenario?
I´m designing small pieces of concrete (imagine chess pieces) with three layers: magnet inside, NFC tag in the middle, and ...
1
vote
1
answer
89
views
Why don't Li-pol accumulators change the polarity of an electromagnet?
I made a simple electromagnet with a screw and a wire.
When I supply power to it via 1 AA battery (1.5v) and change + and - contacts it acts differently with other magnets (attracts and repels), but ...
0
votes
1
answer
108
views
Is there a way to know which magnet pole is facing the circuit?
I am not that much into magnetism, but I am facing the problem of defining the pole of the closest outer magnet it faces the circuit with. The magnet is completely out of control and might as well ...
1
vote
2
answers
1k
views
Winding an electromagnet ring coil to get radial magnetic field
How can I wrap an electromagnet ring coil radially where the north pole is in the center and the south pole is at the outer ring? Is this possible to wrap?
Example:
I know I can wrap a simple coil ...
0
votes
1
answer
2k
views
Where to get the core for an electromagnet?
I understand that using a soft iron core or a ferrite core for an electromagnet increases the strength compared to an air-core. I'm going to be using DC current and want the core to be 5-8mm in ...
2
votes
0
answers
69
views
How to apply Ampere's law with the integration path crossing a permanent magnet?
I read several books on permanent magnet synchronous machines (PMSM), and they tend to describe the relationship between H and B as \$B_{mag}=\mu_0\mu_{r,mag}H_{mag}+B_{rem}\$.
Then when they apply ...
0
votes
1
answer
102
views
Can a "mini" electromagnet propel a magnet 20 cm or so in the air
I have an idea to DIY a little thing that would require to throw a piece about 20 cm into the air (straight up).
My idea is the following: To have a mini electromagnet (such as this one ) and to have ...
10
votes
4
answers
1k
views
Construction for a homogeneous field using permanent magnets
Please let me describe what I am trying to achieve and I will pose my question in the end.
I am trying to design a small chamber which can have a uniform magnetic field inside. I want to see if a ...
0
votes
1
answer
120
views
Off-the-shelf electromagnet with deterministic pole
I looking to buy an electromagnet (12v) and there are a lot of them out there on amazon and ebay in all kinds of size and shapes -some are round, some are rectangle, etc. However, in my application, ...
2
votes
1
answer
80
views
Are magnetic sensors able to pick up the electromagnetic field inside toroids?
From my understanding, correct me if I'm wrong, the electromagnetic field outside a toroid is 0, but it has a EM field within the shell itself. So my question is can a magnetic sensor pick up on this ...
1
vote
1
answer
3k
views
Can a magnet cause a microwave oven to unsafely radiate energy?
I've already successfully warped the colors on a large old CRT Television by setting unshielded speakers on top of it. If I understand correctly, this was due to the deviation of the electro-magnetic (...
0
votes
1
answer
92
views
Permanent magnet generator tooth width
I am thinking about designing a radial flux permanent magnet generator. However, I could not find any information about determining the tooth width. Should the tooth width be all the way the same as ...
0
votes
1
answer
94
views
U Electromagnet Optimization
I have a U shaped magnet (like the one we used to see in school, half red half blue) that I want to make out of it an electromagnet by winding around it a 0.5mm diameter insulated copper wire, ...
0
votes
1
answer
269
views
How to move a magnet to a specific coordinate on a board
I was just reading about Claude Shannon's famous maze-solving mouse, Theseus, which used a movable magnet under the maze to draw the mouse in a given direction. I'd like to play around with this idea.
...
0
votes
0
answers
282
views
How to build a 15,000 Gauss hand-held electromagnet
I'm wondering if it's possible to build a small hand-held electromagnet shaped like a solenoid that is possible of producing a field of 15,000 Gauss.
I'm familiar with the formula for the strength ...
2
votes
1
answer
87
views
A mechano-electro-magnetical control circuit
I came up with the following mechano-electro-magnetical control circuit. The system as depicted here is in equilibrium, i.e. the upper spring s1 is relaxed , the upper circuit is closed (C1 producing ...
-1
votes
1
answer
175
views
Electromagnet Wire/Voltage/Magnets? [closed]
I have some questions about my project. I want to make a big electromagnet, the size is about:
Outer Ring:
50-70cm Height
35cm Diameter
Inner Ring (The Movement):
32cm Diameter
Now:
is it OK to ...
0
votes
2
answers
779
views
Permanent magnet in ac motor
Is Magnet in pmac motor degrade while they are in use because in tesla model 3 they uses pmac motor so we have to replace magnet frequently ?
-1
votes
1
answer
2k
views
Magnetic Lock Power Source
I have just installed a 12v 350mA 600lb Electrical Magnetic Interior Door Lock. I have tested it with a cheap 12V, 1A DC Switching Power Supply Adapter and it works just like it was designed. I have ...
4
votes
6
answers
10k
views
Using Neodymium Magnets as wire connectors? [duplicate]
A new project I'm working has to be highly modular. All the electronics will be hidden in a case, so I was wondering if there's any way to use magnets and pass current through them for the project?
...
0
votes
4
answers
433
views
Can an alternating magnetic field be "informationally" shielded?
I have asked previously about the properties & shielding of the "static" magnetic field previously, where I have determined that static fields are hard to shield.
However what I am really ...
0
votes
1
answer
882
views
Can two magnets damage or interfere brushless motor?
I want to get the absolute position of motor shaft, so I have added two magnets on the metallic thread (which holds the motor) and some hall sensors on top of shaft.
Can the magnets in some way ...
15
votes
3
answers
4k
views
Does Shielding "Electrically" shield "Magnetically" too?
I know it sounds like a newbie question but I can't wrap my mind around it. An electromagnetic field is electric + magnetic field.
So this means that when shielding an equipment offensively, for ...
0
votes
2
answers
535
views
What is the magnetic field due to an electromagnet at a point that is not along its axis?
For e.g. at a point below(or perpendicular) to a cuboidal/cylindrical core electromagnet?
I am confused whether the magnetic field for an iron-core electromagnet is limited to the axis passing through ...
2
votes
2
answers
3k
views
Are ferrite beads supposed to be magnetic?
I have replaced the ferrite bead on my audio cable with new ones that I just bought. But I have tested them and they aren't magnetic, it's just like a cylindric metal inside it, but I thought it has ...
1
vote
4
answers
2k
views
Measuring an electromagnet
I'm working on a project. I'm going to use a 'pulsing' electromagnet, and want to know how much power it's draining.
Is it just a case of, if I'm using a 12 V battery for example, then I'm using 12 V? ...
1
vote
1
answer
9k
views
How much does the power of a magnet increase voltage on electromagnetic induction?
Searching through the site i found some useful info saying that a powerful magnet means more voltage, but i'd like to know how much does the voltage increase in relation with the magnet power (Given a ...