How Does Maxwell's Current Term Suggest Light is an Electromagnetic Wave?

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commelion
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yo

ok progress on the electromagnetic wave front is progressing nicely...finally, but

i have stumbled on a area that i need some help with. see below

when maxwell took amperes law, he added what's known locally ! as the current term, this was done because he realized that a changing magnetic field gives rise to an electric field.

Q how does this current term suggest that light must be an electromagnetic wave ?

if anyone has any consise explanations i would appreciate it, i don't need the maths as i have them in front of me. just think of it as a table quiz kind of answer !

thanks in advance
 
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commelion said:
yo

ok progress on the electromagnetic wave front is progressing nicely...finally, but

i have stumbled on a area that i need some help with. see below

when maxwell took amperes law, he added what's known locally ! as the current term, this was done because he realized that a changing magnetic field gives rise to an electric field.

Q how does this current term suggest that light must be an electromagnetic wave ?

if anyone has any consise explanations i would appreciate it, i don't need the maths as i have them in front of me. just think of it as a table quiz kind of answer !

thanks in advance

Light is just EM wave in much higher frequency spectrum. It is a frequency thing. I am not good enough to explain in plain English, from my understanding:

[tex]\nabla \times \vec H= \vec J +\epsilon_0 \frac{\partial \vec E}{\partial t}\;\Rightarrow \int_c \vec H\cdot d\vec l = I_ C+I_D\;\;\hbox { where it is conduction current and displacement current respectively.}[/tex]

This just said a varying conduction and/or displacement current will produce a varying magnetic field. Which in turn the varying magnetic field will be accompanied with a varying electric field by:

[tex]\nabla \times \vec E =-\frac {\partial \vec B}{\partial t}[/tex]

But nothing is said about the frequency. As said, light is just the upper range of the EM wave frequency.