All Questions
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Principle of working of a transformer [closed]
What is the principle of working of transformers?
Magnetic effects of current
Mutual induction
Self induction
Chemical effects of current
I know that Mutual induction is the right answer, but isn't ...
user319029
1
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2
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On a nanoscopic level, what really happens to the electrons in the secondary coil of a step-up transformer?
I know that when AC is passed through the primary coil of a step-up transformer a higher emf is induced in the secondary coil (with more turns) of the transformer. Since energy is conserved, and P = ...
- 337
7
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5
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How to generate electric current without a permanent magnet?
The question is pretty simple:
Can we build a device that coverts mechanical work in electric current1 without employing a permanent magnet and without access to any external source of current?
The ...
- 4,577
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3
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Why does the power remain constant during the stepping up and stepping down of current in transformers?
I understand quite a bit of transformers, their structure and other concepts and formulas related to mutual induction. However I'm not able to explain why the electrical power has to be constant ...
user248823
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2
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837
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Can current be induced in a spinning wire due to Earth's field
I came across a scenario where two people are spinning a wire with no specific magnetic field:
In such a scenario, can any current be induced due to the change in magnetic flux (where the magnetic ...
- 15
1
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1
answer
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Two types of electric field
My textbook mentions that electric field produced by electric charge and that produced by changing magnetic field are different in nature.
After searching from various sources I found that electric ...
- 135
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3
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971
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Why EMF induced in the coil acts to oppose any change in the magnetic flux?
This might be an absurd question for some of you guys.
According to Lenz's Law an induced current will create a magnetic field that induces another current in which it opposes the current causing it ...
user215726
7
votes
1
answer
95
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Why would a steel tube vibrate under high voltage?
Can anyone explain why a vertical steel tube, standing with one end in contact with the ground under a $230 \space kV$ electric transmission tower, would physically vibrate at high frequency? I'm not ...
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What is magnetic flux? How is it related to Faraday's law?
For example, how do we explain Faraday's wheel using Faraday's law? There should be no emf induced since the flux is constant. Also, if we are given a magnetized material, and we somehow manage to ...
- 254
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2
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Coil Inducing a Back Emf in its Own Circuit
For this above question, how is even a back emf induced in the circuit because of the coil. Doesn't Faraday's Law say the a change in flux threading an external coil will induce an emf. So then how ...
- 203
2
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1
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301
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Does terminal voltage decrease as we draw current?
If the secondary is an open circuit or the current taken from it is small, then to a good approximation $ ε_s = v_s$ where $ ε_s$ and $ v_s$ are secondary voltage(induced) and secondary terminal ...
user117954
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2
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How is it possible to even develop any current in an inductor?
Potential difference across an inductor (ie p.d. between current exit point and current entry point) is given as
$$V= -L\frac{di}{dt} -iR,$$
where $L$ is the inductance of inductor and $R$ is its ...
- 121
3
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2
answers
659
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Does the skin effect and the proximity effect cancel each other out?
I'm interested in how the Skin Effect and the Proximity Effect interact with each other.
From what I can understand:
The Skin Effect is when AC current 'collects' on the skin of
conductors due to ...
- 33
2
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2
answers
2k
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Is it possible to use induction ampermeter to measure power consumption of electric water heater and dryer?
I hope this practical question is not OT and not too trivial for this forum. I am renting an apartment in a duplex with a shared water heater and dryer. Turns out, both water heater and the dryer are ...
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