One point that I"m surprised to know is the light is also called an electromagnetic wave.
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Does this include light of any type of kind, for example: light from a bulb, a tube, and likewise from the Sun?How perform they save electric and also magnetic fields?
Well, I would say the electromagnetic field is the medium.
For favor the medium water oscillates when a water tide is observable after cram a stone, therefore the electromagnetic ar oscillates when excited by one antenna, say. If nothing oscillates there room no waves, neither in water nor in the electromagnetic field.
The tool disappears only as soon as one think of one electromagnetic field as being nothing, just a vacuum. But this liberal check out of the vacuum is quite various from the watch of the vacuum in QED, the accepted theory the electromagnetic fields. There the vacuum state doesn"t own an electromagnetic field. An ext precisely, that expectation value - i.e., what is observable around it - is identically zero.
Yes you are fully right, but it took an intellectual revolution for physicists to realise that it made sense to have a tide that wasn"t the motion or jiggling of some physical medium, a tide that might exist equally fine in empty space.
All light is electromagnetic radiation. However to questioning « exactly how do lock contain ... » is a small vague or philosophical. The correct answer is, the light is the field.
By the way, over there isn"t yes, really a difference between the electric field and the magnetic field, they jointly compose one electro-magnetic field, and this one field cannot really be divided into two separate parts, one electric, the various other magnetic, since two different observers who are relocating in various directions would divide the same ar differently, what one referred to as electric, the other observer would call magnetic, reflecting that the department into two parts is rather artificial.
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Finally, to answer perhaps what you yes, really meant, just how does the light bulb or whatever contain the field, the answer is it doesn"t exactly at first, but turning on the existing of power that flows v the filament produces activities in the electron in the atom in the filament at simply the right speeds so that that activity of the power in the atom generates a magnetic field and also that start the entirety process. In its an essential principle, that is the same just like a radio antenna, yet the frequency that the movement is different so the electro-magnetic field created is at a radio frequency instead of a light frequency, and also there room other distinctions of information also. I will not explain about how atoms emit photons because that, in a way, is already contained in what ns said, I simply said that in the wave picture of classic electromagnetic theory rather of in quantum terms.