All Questions
11 questions
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47
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How does DC loses energy?
I am new to it, so please help. As I know, AC current is back and forth motion of electrons, which radiates electromagnetic waves, so there is energy radiation from power line to our home. But in case ...
2
votes
1
answer
142
views
Current produced by EM wave in circuit
I have a specific question regarding the current produced by an EM wave interacting with a simple square circuit with constant resistance $R$. Let's say the EM wave can be explained by the simple ...
- 161
0
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2
answers
49
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Why is there an upper bound to the frequency at which an electronic device can be operated? [closed]
Why is there an upper bound to the frequency at which an electronic device can be operated? For example, the frequency of electricity that we receive at home is 60Hz (in the USA).
What will happen if ...
- 1,437
0
votes
3
answers
555
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Phase difference between source voltage and inductor voltage
What will be the phase difference between the source voltage and the inductor voltage? Will the two voltages be in phase or will be out of phase. How much out of phase they will be?
Note that there ...
- 1,453
1
vote
0
answers
35
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creating a varying electric field across a copper strip
Hi I am trying to create a varying electric field (by position on copper strip) across a copper strip by attempting a standing wave pattern. the following is a diagram
may I have some guidance on how ...
- 111
4
votes
1
answer
497
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What is the theoretical maximum efficiency for LEDs?
Whatever efficiency you want to give in converting electricity to light. I'm guessing it would depend on the type of LED. I imagine limitations come from various reasons. It would be cool if there ...
user234190
2
votes
4
answers
796
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Is the vacuum permittivity a result of defining other units first?
From Coulomb's law
$$F=\frac{1}{4\pi\epsilon_0}\frac{q_1q_2}{r^2}$$
If instead we defined the charge of a coulomb to be $\sqrt{\epsilon_0}$ times it is now, the force would be exactly the ...
- 191
1
vote
0
answers
97
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Could the tether of a space elevator be used as a single-wire transmission line?
If you're unfamiliar with single-wire transmission lines: https://en.wikipedia.org/wiki/Single-wire_transmission_line
It seems that a material with high conductivity (eg: certain configurations of ...
- 111
0
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1
answer
38
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Does power dissipate on real conductor when charge move from charged object to neutral charged object?
for example we have charged sphere and we have neutral charged sphere
After we connect them with real conductor (few Ohm resistance) some charge will move from charged sphere to neutral sphere.
Will ...
2
votes
1
answer
119
views
Toroidal shaped Tesla Coil
Since toroidal shaped transformers perform better than conventional E core transformers. Would a Tesla Coil that is shaped in a toroidal shape perform better than Tesla coils that is shaped ...
- 133
1
vote
1
answer
15k
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Why the electric bulb turns on almost instantly when the switch is closed? [duplicate]
The electron drift speed is estimated to be very low.How could there is current almost the instant a circuit is closed??
By the discussions it is known that The information about beginning of the ...
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