Questions tagged [electromagnetism]
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 the site.
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Why can't waveguides support TEM waves
I found a couple of answers
"the H field is supported by induced currents in the walls and the E field is supported by induced voltages in the walls and in order for the wave to propagate these ...
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BJT-based Induction Heating circuit not heating anything
Recently I tried to build small induction heater powered by low voltage. I don't have any MOSFETs (and most of the schematics in the internet are based on ZVS circuit), but I found a single BJT NPN ...
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How can I accurately simulate the radiation resistance and gain of an extremely electrically small (λ/100-λ/500) structure?
For my research, I need to determine the radiation properties (radiation resistance, efficiency, gain, pattern, etc.) of some on-chip devices that are anywhere from 1/100 to 1/500 of the free-space ...
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Smith Chart Verification - Transmission Line Load Impedance
I’m struggling a bit with the Smith chart and tried to solve the following exercise. I would appreciate it if someone could check whether my Smith chart construction and reasoning are correct.
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How to calculate this TI EMI filter design?
I have a TI reference design for my project and now I need to do the calculation for the EMI filter to know how they designed it. I attached the reference PDF.
Does anyone know how to design it and ...
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Does delta V*I represent the power that is "used up" by a portion of the circuit, or is it the power transferred by it onwards?
If one computes the direction of the energy flux into a circuit using the Poynting vector, one finds that it points into the surface of the wire from outside the wire. In this view, it seems natural ...
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Modelling the load presented by a short stub of centre conductor at the end of a coax
I have a small length of the centre conductor sticking out of the outer conductor at the end of my coax. I want to estimate the load this centre conductor "stub" presents to the coax at 3 ...
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Opposing induction within a symmetrical parallel circuit
I have the following circuit, where a DC-V1 has 15 V applied in parallel to resistors R1 and R2.
Two homogeneous magnetic fields of equal magnitude (B1 - into the page, B2 - out of the page) are ...
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How to derive a geometric EM model from measured S-parameters (openEMS + Qucs)
I’m getting into high-frequency simulation and PCB design and I need help understanding how to bridge circuit-level S-parameter measurements with EM simulation.
I want to characterize a 2-pole Wago ...
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Can a magnetic loop antenna be used to communicate through a perfect metal container?
I understand that in the near field of a loop antenna the magnetic field dominates, before it has formed a radiative propagating EM wave. Based on this, and the fact that magnetic fields can penetrate ...
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Confused about Work done in moving a charge from infinity to a point
Let us consider a charge \$Q>0\$ at origin. Let \$P(r,0)\$ where \$r>0\$ be on \$X\$ axis.Consider a point \$M(x,0),\:x>r\$ from which we have to move a charge \$q>0\$ towards point \$P\$.
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Energy Conservation in an Induction Heater with a Transformer
Apologies for the simple question, but I can't understand the energy conservation in the following scenario.
I am trying to build an induction heater using a few MOSFET gates, diodes, capacitors, ...
user620952
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Would this motor growler from a microwave oven transformer work? (Drawing included)
I want to make a growler to test motor rotors / armatures.
I want to use a microwave oven transformer, removing the secondary coil, cutting the centre out (where the two red lines are) and removing ...
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Capacitor electron flow and discharge
From my current understanding, a capacitor has an insulator between two plates one of which is negatively charged and the other is positively charged attracting them to each other and storing the ...
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Can I drive a Helmholtz coil with an audio amplifier?
For my personal project, I want to drive a Helmholtz coil of 8 ohms with 100Hz signal.
My current setup looks like this:
Function Generator (FY3200S series DDS Function Signal Generator)
Audio ...
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