Helo. I was watching walter lewin lecture on electromagnetic waves, and since its a prerecorded video, i cant raise my hand and ask a question, and so i am here. The math is a foreign language to me so explaining with equations wont help me understand. Im a visual learner. Visual examples will help me understand best. Im confused as to what the electric and magnetic fields are being emitted from and im wondering what is happening that makes those two fields collapse and rise in synchronicity. Thanks in advance for helping me understand.
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Have a look at this and this. As in Mozibur's answer below, the electric and magnetic fields are manifestations of the same phenomena. – joseph h Oct 16 '21 at 05:37
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What are photon, EM radiation and radio waves: https://physics.stackexchange.com/a/253957 – HolgerFiedler Oct 18 '21 at 04:35
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Im confused as to what the electric and magnetic fields are being emitted from
The fields aren't emitted from anywhere. A (vector) field is just a vector associated with every point in space. The electromagnetic field simply exists everywhere at all times.
Waves in the field can be emitted from many different sources. Classically any accelerating charge produces an electromagnetic wave. This could be the electrons moving back and forth in a dipole antenna to send radio waves from a broadcast station to the radio receiver in your home. Or it could be the thermal motion of electrons in a material producing (some approximation of) blackbody radiation. When the object is very hot (for example, the sun) this radiation can include a substantial amount of visible light, as well as the infrared radiation that we feel as radiant heat.
In modern physics we also learn that EM radiation can be produced when a charged particle changes energy states. For example when an LED or laser produces light.
and im wondering what is happening that makes those two fields collapse and rise in synchronicity.
As mentioned in a previous answer, the electric and magnetic fields are simply two aspects of one underlying electromagnetic field.
The Photon
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The two fields only appear to rise synchonously because in fact, thete is only one field that is changing. It's rather like saying why do the two sides of the paper roll up when I roll up one side? In fact, you are not rolling up one side, you are rolling up a page and the two sides are simply an aspect of that one page.
Mozibur Ullah
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