The kind of magic without which all of this wouldn't be possible. This tag should be used for questions about the **physics** of the fields that charged particles create and how these fields interact. It should not be used for all questions involving electromagnetism, that would be everything on ...

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3answers
55 views

Can Copper Magnet Wire have layers in a coil?

I know Magnet Wire has a thin layer of insulation but when i make a coil, can I stack/layer the wire on top of each other or will it just perform the same with normal wire.
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1answer
58 views

Cause of skin effect: eddy current inside conductor

We all know very well that due to eddy current (back EMF) generation within an AC carrying conductor, "skin effect" occurs. Eddy current density: Highest at center of conductor core Lowest at ...
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1answer
44 views

How does inductance change with presence of different directional magnetic fields?

If I design a coil driver for a certain application, I assume there is a fixed load right? It may have drive any inductance between an interval but you can not drive any coil, because the driver is ...
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1answer
67 views

electromagnet repelling permanent magnet [closed]

I have an electromagnet (turned off) with an iron core in front of a permanent magnet. At this stage they attract each other. Will any current do if I want them to repel each other, or is there a ...
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1answer
48 views

How to run ammeter in low resistance?

I need to measure current in a small electromagnet powered off 3 x AAA batteries in series. This is the manual for my multimeter. When I run this multimeter in series and try to find the current, the ...
3
votes
1answer
34 views

How to find the polarization (phase) of the virtual source if image theory is used

Consider a radiating element (actual source) is placed above a ground plane, and if we apply image theory to determine the E-filed, the virtual source will be placed below the ground plane and ground ...
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3answers
81 views

is there any impact of Electron's spin in CRT?

fact-1. Electron's (or any-other particles) magnetic behavior depends upon mass, charge and spin. fact-2. All electrons are not the same. Though all electron have the same mass and charge; an ...
2
votes
6answers
96 views

Controlling the frequency of AC used to energize an electromagnet

I am trying to build an electromagnetic pendulum which essentially has a pendulum arm with a permanent magnet at its end which is 'kicked' by an electromagnet placed at the mean position to drive the ...
-2
votes
1answer
33 views

In electromagnetic inductance, which one is more efficient, to focus all power to move one part or split it to move both at the same time?

Assuming equal force is used, which one would be more efficient when it comes to generating current through electromagnetic induction: to use 100% of available force to move the permanent magnet only ...
-2
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1answer
38 views

can something have electricity flowing in it without being connected to electricity? [closed]

Can something have a powerful electronic flow throw it that's remain constant for a very long period of time if it was somehow electronically charged before hand?
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3answers
79 views

Electrical Load increase on Generator = More Fuel Consumption

Why does more electrical current drawn from generator leads to more fuel consumption? I understand that it's due to conservation of energy, I just want to know what the phenomenon or reaction is ...
0
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1answer
51 views

Building a magnetizer

I'm building a simple magnetizer for the realization of a physics experiment, bought yesterday components for the construction of the same, I am following the scheme of this site: The final ...
0
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1answer
69 views

Magnets in Transformers Desgin

What is the advantages, and disadvantages of using neodymium magnets instead of ferrite cores in transformers? How would the magnetic flux density vary of such a transformer utilizing a neodymium ...
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1answer
80 views

How to calculate energy transfer in inductive heating?

I designed an inductance heater. Its inductor is calculated 50 uH as below: And I draw 9.4 A AC current at 33 Khz of it. But, I want to know how to calculate the transferred energy to the ...
-2
votes
1answer
72 views

Coil Gun Schematic [closed]

I have a question. I have been looking at making a Coil gun lately and i had an idea for a simple one. Just need to know if it would work. Basically: Battery-->Switch-->Diode-->Transformer-->Coil For ...
0
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1answer
40 views

Electric motors with both stater and rotor as electromagnets [closed]

I am totally new to the Electrical area. I wanted to do a project on Electric car which needs an Electric motor which is highly powerful and efficient. Are there any motors which have both stater and ...
0
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0answers
30 views

By measuring the electricity generated, is it possible to calculate how fast the turbine was moving?

Say a wind turbine is moving at varying speeds. From the electricity it generates, would it be possible to calculate/replicate the motions of the turbine? How accurate can these measurements be? Will ...
0
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1answer
75 views

Ripple flowing through probes connected to the same point!

While trying to filter the ripple of my switching PSU, I've come to a phenomenon that is probably well known to professionals, but seems absurd to me. Admittedly, my scope is not of the highest ...
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votes
2answers
64 views

Perpetual motion desk toys and magnets [duplicate]

As far as I know, perpetual motion orbital desktops like below use an electromagnet in the base. Why aren't permanent magnets used on both ends instead? Does anyone know where I could find a ...
1
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0answers
37 views

Why compass module is affected by its x,y position, if my phone's compass work in the same environment?

I am using hmc5883L on an autonomus robot. It shall remain in a 1 meter squared area. I have recently discovered that its reading changes up to 20 degrees on different positions even when it is facing ...
0
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1answer
77 views

Range of Electromagnetic Waves/Radio waves? [closed]

What basically determines that how far the electromagnetic waves will travel away from the source ? In our world where there is air and other materials how electromagnetic waves would generally ...
1
vote
1answer
44 views

Magnet Wire AWG?

I need some magnet wire for a school project, it will be wrapped around a ~5cm nail and powered by either a 9v or a couple AA batteries. It won't be doing any heavy lifting or anything, just some ...
0
votes
3answers
82 views

Electromagnetic Radiation and Communication! [closed]

I read that the accelerated charges create electromagnetic field/spectrum which consists of following different waves: gamma X-rays ultraviolet visible light infrared microwaves radio waves gamma,...
0
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1answer
45 views

4x4 Switch Matrix Problem Please Help [closed]

we are trying to built Electronic Locker Which is Controlling by a specific Combinational Password but we have a Problem with (4x4 Switch Matrix Numbering Order) In the Circuit Diagram the numbering ...
0
votes
1answer
34 views

Low weight split core transformer on 11kVA transmission line

I've seen transmission line energy harvester's that utilise a split core transformer. Here is an example. However, I fail to see how this is possible when a transformer cores which are small enough ...
0
votes
1answer
29 views

converting inductance to electromagnetic force

How might one determine the amount of electromagnetic force produced by an unshielded inductor? E.g. How much holding force does a 600uH unshielded inductor posses? Or alternatively in reverse: How ...
0
votes
1answer
73 views

Electromechancial locks used in a turnstile

I was looking to build a RFID operated turnstile similar to picture below. I will have RFID readers on both ends where the door would open from either end only if the RFID is authenticated on either ...
0
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0answers
31 views

How do I calculate magnetic flux density?

Calculate (for the kinked line conductor) the magnetic flux density (vector) at the place P. I know i should use formula: \$\vec{B}= \frac{\mu_0I}{4\pi\rho} \left[\sin(\alpha _2)-\sin(\alpha _1)\...
0
votes
1answer
40 views

Effects on the exterior magnetic field from a field induced by a wire?

I have an experimental set-up where I place a conductive wire in a magnetic field created by an electromagnet like so: There is current flowing in a wire as well(aside from the electromagnet) ...
0
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0answers
40 views

Why Can Capicators Have All Their Charges Separated?

Conceptually, if a molecular structure separates all of its charges, like in the 2 plates of a capacitor, this should leave a uniformity of charge either holes or electrons with a large voltage ...
0
votes
2answers
80 views

Wireless energy scavenging from in-home wiring EM fields

I was wondering if it would be possible to power a little 3.3V microcontroller, by harvesting an electromagnetic field around an in-wall insulated 240V 50Hz AC power cable. Something like contactless ...
1
vote
1answer
21 views

\$2n\$ point charges on a circle at \$O\$, what's total electric field intensity \$\overline{E}\$ at \$\pm 1\mathrm{m}\$?

The problem reads is from a Schaum's Outlines of EMFT and reads: A total charge of \$1\mathrm{nC}\$ is equally distributed among \$2n\$ points which are placed equidistantly on a circle with \$1\...
3
votes
1answer
54 views

accuracy of magnetic field sensors in electrical vehicles

For coordinate system alignment purposes, as demonstrated in the figure, I want to use the smartphone's virtual orientation sensor. However, the virtual sensor is using a combination of acceleration, ...
0
votes
1answer
88 views

Designing a generator

I am modeling the output voltage of an AC generator and I am using/I chose the following specifics: Number coil turns = 300. This is 1.02 mm gauge copper wire, so knowing the density of copper, I ...
0
votes
1answer
66 views

How to increase an electromagnet's magnetic field size

So i made this electromagnet out of a microwave oven transformer by taking out the secondary coil. It very strong but it can only attract the metals if i bring it really close. How do increase the ...
0
votes
1answer
33 views

Controlling an electromagnetic switch with Reed switches

I'm trying to power a 12v electromagnetic switch using NO reed switches. IE: when the 5 reed switches all have magnets near them then the elecromagnet switch unlocks something. However, I'm trying ...
1
vote
0answers
45 views

Calculate induced voltage in a wire due to mains wiring

I wish to calculate voltage induced in a short piece of wire of known length, due to mains household wiring carrying some current say 5 amps. My application is biomedical sensor wire and I can not use ...
0
votes
1answer
47 views

How does a moving magnetic field cause motion in the Al strip rotor?

Consider the following information: https://www.youtube.com/watch?v=7snjbmdYlDI How would you explain how the moving magnetic field causes motion in AL labeled rotor?
4
votes
1answer
103 views

How can I describe mathematically what is happening in my home made LVDT variant?

I've built an LVDT (Linear Variable Differential Transformer) that is a little different than how it is conventionally done with 2 secondary coils positioned adjacent to a primary coil. My design is a ...
-5
votes
1answer
46 views

Produce current

Ok, so I was trying our an experiment to generate minute current. I got a battery operated gear motor which can produce current to light ant led bulb when rotated. I am trying to create an automation ...
-1
votes
1answer
160 views

DC generator without permanent magnets

I have heard that there are DC generators where resistance can be regulated by using electro-magnetic field. Where permanent magnets are substituted with electro-magnets. Are this kind of generator ...
-5
votes
1answer
63 views

Build 0.5 T solenoid with [closed]

I want to build 0.5T solenoid (Length 30 cm and diameter 0.5 cm). Can anyone provide me the formula taken into account the length, radius of the solenoid and Radius of wire, i.e. Outer radius after ...
-2
votes
2answers
89 views

Should I get EE or CS major? [closed]

I don't know whether this is the place to ask this. I'm sorry if this is the wrong place. I'm a first year university student in Electrical Engineering and Informatics School. In my second year, I ...
0
votes
2answers
53 views

Will this structure emit EM waves when excited by out-of-plane time varying magnetic field?

Say I create a structure from copper that looks like the figure shown below. It's an open circle whose ends terminate in protruding wires of length x. If I excite this with an out-of plane time ...
0
votes
2answers
94 views

Increasing efficiency of a kinetic energy battery charger

I want to use Faradays law to convert the kinetic energy from actions such as a jog/shake to produce electricity to ultimately charge a battery. Materials Neodynium Magnet 3/4 diameter (2) ...
0
votes
2answers
87 views

Ways to use electromagnets to pick up metal shavings at a distance

I work at a rotor machining plant and there is an issue for shutting a line down to clean up metal shavings, causes too much down time. I was thinking of using a strong electromagnet to have a "pick ...
0
votes
1answer
55 views

Propagation across a surface

How do stud sensors actually sense current, what would cause the effect to propagate across an 8x8 foot surface area and remain strong enough to be detected? I asked another group "what is happening",...
0
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1answer
49 views

Formula for electromagnet strength parallel, outside the coil

I am working on a electromagnet project to collect metal shavings off the floor after machining. I have a formula for the magnetic strength at a distance from the ends, but not parallel to the coil. ...
0
votes
2answers
37 views

Can we make a simple wireless device by mutual induction phenomenon

I want to make a simple wireless device (radio?) that consists of only two copper coils where changing magnetic flux in primary coil causes a current flow in the secondary. I tried, once, with LEDs ...
0
votes
1answer
93 views

Magnetic switch with no moving parts

Is there a magnetic switch (like a reed switch) but with no moving parts? I need a switch that can be turned on by a magnetic field but won't move around due to tremendous shock absorption.