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 electromagnetic field is light. So will I see light? A ray of light or something when I create a varying electric field?
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1light is a very small part of the electromagnetic spectrum, between NUV (near ultra violet) and NIR ( near infrared ) https://en.wikipedia.org/wiki/File:Light_spectrum.svg inhttps://en.wikipedia.org/wiki/Electromagnetic_radiation – anna v Apr 18 '22 at 17:59
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1So (developing Anna v's comment) you'll make an electromagnetic wave, but unless your fields are changing at the a frequency in the right band (between about $4.3 \times 10^{14}\ \text {Hz and}\ \ 7.5 \times 10^{14} \text{ Hz}$) the wave will not be visible – your eyes won't detect it. – Philip Wood Apr 18 '22 at 18:46
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I like your question! fyi I've just asked Has anyone ever put an electrostatic dipole on a rotating shaft, spun it and demonstrated reception of a propagating wave in the far-field? – uhoh May 16 '22 at 21:05
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Yes, that's correct in principle.
For visible light, the changes have to occur on time-scales of a femtosecond, $10^{-15}$ seconds, and on spatial scales of about a 100 nanometers, $10^{-7}$ meters, so you have to make the changes very quickly and in a very small space. Usually what you see comes from a whole bunch of little electrons wiggling around very fast.
Roger Wood
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It is not very difficult to generate radio waves with oscillating electric fields. Microwaves were a challenge. – R.W. Bird Apr 18 '22 at 20:41