All Questions
11
questions
1
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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 ...
- 5,819
1
vote
1
answer
112
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Why does the kink has the following vector direction?
I imagine the kink to be the following image in the EM wave.
On the image, we see the charge movement 2 times and each one is very small movement. Even though it is small, it is easy to see why each ...
- 525
26
votes
2
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7k
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Is it (practically) possible for a large building to be a Faraday cage?
In my sophomore year of high school, my P.E. teachers kept on complaining about how phones didn't have a network connection in our gym, regardless of model, service provider, etc. A couple of feet ...
6
votes
3
answers
2k
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Feynman on Inverse Square Law of EM Radiation
I've been reading through (and listening to) a collection of lectures form Richard Feynman's Lectures on Physics. In lecture #2, titled "Basic Physics", he makes the following statement:
Although ...
2
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3
answers
1k
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How do near-field EM fields change to far-field EM waves at an antenna
What is the mechanism by which the near-field non-traveling electromagnetic fields in the vicinity of an antenna are changed into the far-field electromagnetic waves traveling at the speed of light? ...
- 249
1
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1
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If I create a varying electric field and it will then create a varying magnetic field, so will it also create light? Will I see a light ray?
If there is an electric field which is changing in time, lets say I create one, then it should create a varying magnetic field. So that means that there is an electromagnetic field, and oscillating ...
1
vote
1
answer
273
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Do Electric fields really contain energy in them? [closed]
If we assume that energy was first absorbed by q1 and then released by it which then reaches q2 , the same as , electric field not being absorbable and somehow magically gives the energy to q2 and q1 ...
1
vote
1
answer
90
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Name of electric force
during a lab experiment, i noticed that a metal ball has a much harder time rolling on metal rails when their is a current passing through it and the rails. I was wondering why and if there was a name ...
- 1,473
1
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0
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84
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Why are not kinks produced for constant speed charge?
Why arent kinks produced when the charge moves at constant velocity in the same linear direction ?
I am asking this because this is the backbone of why EM wave is not created for constant velocity ...
- 525
0
votes
2
answers
216
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Electromagnetic Waves and Inertia
I have a conceptual question. Suppose we have two bodies of equal masses. One is electrically neutral and the other is electrically charged (positivley charged). Now we apply equal magnitude of force ...
- 2,517
0
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1
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203
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How can we use the electrostatic boundary conditions for electromagnetic waves?
The boundary conditions for an electromagnetic wave passing from one linear dielectric media to the other (both having no free charges or current) are taken as:
$$B_{\perp_1} -B_{\perp_2} =0$$
$${\...
- 2,000