Mohamed Khairy, A student
- Definition : Its the loss of electromagnetic energy propagating inside a dielectric.
-Why it happens? well two reasons, one is the relaxation effects, basically the oscillating electric field polarize the dielectric (that is why its "di"electric) and this creates a dipole that is also oscillating, this dipole absorbs and then rescatters the electric field . Of course this response is not instantaneous , the dipole's response is always delayed by some phase with respect to the field. Now what if the oscillation frequency increases to the extent that by the time the dipole starts to respond in one direction the field switch its direction, well the momentum gained will be lost in the switch, imagine stirring a cup clockwise and then suddenly stir it anti-clockwise.
The second reason is resonance, when the electric field's frequency resonates with the electronic/vibrionic/rotational transitions of the dielectric , the dielectric will "absorb" the energy in order to perform such transition and the energy will dissipate and you get losses (this is the physics behind the controversial issue of global warming :D seriously)
-Why it happens? well two reasons, one is the relaxation effects, basically the oscillating electric field polarize the dielectric (that is why its "di"electric) and this creates a dipole that is also oscillating, this dipole absorbs and then rescatters the electric field . Of course this response is not instantaneous , the dipole's response is always delayed by some phase with respect to the field. Now what if the oscillation frequency increases to the extent that by the time the dipole starts to respond in one direction the field switch its direction, well the momentum gained will be lost in the switch, imagine stirring a cup clockwise and then suddenly stir it anti-clockwise.
The second reason is resonance, when the electric field's frequency resonates with the electronic/vibrionic/rotational transitions of the dielectric , the dielectric will "absorb" the energy in order to perform such transition and the energy will dissipate and you get losses (this is the physics behind the controversial issue of global warming :D seriously)
https://www.quora.com/What-is-dielectric-loss
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