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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62 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
49 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 ...
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1answer
60 views

Coil Gun Schematic [on hold]

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 ...
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1answer
35 views

Electric motors with both stater and rotor as electromagnets [on hold]

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 ...
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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 ...
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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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2answers
54 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 ...
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0answers
33 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 ...
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1answer
75 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 ...
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1answer
43 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 ...
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3answers
79 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 ...
0
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1answer
42 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 ...
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1answer
33 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 ...
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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 ...
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1answer
67 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 ...
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0answers
27 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 ...
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1answer
36 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) ...
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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 ...
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2answers
77 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 ...
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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 ...
3
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1answer
51 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
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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
59 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 ...
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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 ...
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0answers
44 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 ...
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0answers
27 views

Eddy currents of a single thin wire

Given a copper wire length of 2m, and a diameter of 1mm moving in a strong magnetic field(1T+) at a high velocity(20m/s), is it reasonable to assume the Eddy currents = 0? Due to their small area, ...
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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?
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1answer
94 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 ...
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votes
1answer
44 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 ...
-2
votes
1answer
123 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
55 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
86 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 ...
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2answers
93 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) ...
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2answers
77 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
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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 ...
0
votes
1answer
46 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
35 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
86 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.
0
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2answers
90 views

Reactive Power in Inductor and Capacitor

Suppose a RLC circuit with AC source. Why the net reactive power in the circuit is the difference of reactive power in the inductor and the reactive power in the capacitor ? As both of them store ...
0
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0answers
47 views

There is thermochromic pigment. Is there a magnetic variety of pigment?

I can mix thermochromic pigment with transparent epoxy resin into a brightly colored paste which changes colors when it detects a temperature threshold in the surface it is applied to. Is it ...
1
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3answers
127 views

Complex impedance of a transformer

I consider only an ideal transformer here (no leakage etc.). Let L1 and L2 be the induction coefficients of the primary and secondary resp., and M be the mutual induction coefficient. Assume that the ...
1
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3answers
134 views

Reactive Power in the circuit

Why is inductive reactive power considered positive while capacitive reactive power is considered negative in the circuit ? Both inductor and capacitor consume apparent power so I guess ...
0
votes
4answers
176 views

Make an electromagnet attract and repulse

I bought and electromagnet online hoping to make it attract and repulse metals changing the polarity of the voltage on it, but I ended up experiencing attraction all the time. Is there any way to ...
0
votes
1answer
66 views

What method do wireless routers use to break apart the received wave into different frequencies?

What method do wireless routers use to break apart the received wave into different frequencies ? Does it have anything to do with Fourier Transformations ?
-2
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1answer
74 views

ionizing body with tesla coil?

I have made a tesla coil.Now I want to ionize my body with it so that I can give shock to people with my hands.Is it possible to shock someone with it?
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1answer
50 views

Welding Transformers?

I was thinking of making a carry handle for two microwave oven transformers in series, and also so that they can share a common ground without having to split the ground wire. I thought about bolting ...
-1
votes
1answer
67 views

What are the options for short range under six inches 3D multi point location tracking?

What methods exist to track the position of points relative to each other. Particularly what methods allow the determination of the distance between up to ten points at once. The distance ...
1
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0answers
36 views

Torque and Current Frequency Relationship in Lorentz force

Lorentz force equation shows us that current is proportional to the force. Is it safe to assume that the force generated by an AC current at 60Hz will always have the same frequency? In other words, ...
1
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3answers
100 views

Hall effect device for circa 1 tesla gaussmeter

I'm thinking about building an unsophisticated bench instrument for measuring magnetic field density, just to support my learning about electromagnetism and building magnetics for power electronics ...