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$$\oint B.dl = \mu_0\left(I+\epsilon_0\frac{\partial\Phi_E}{\partial t}\right)$$ Please explain the applications , and implications of the modified Ampere's circuital law with Maxwell's addition. Especially, significance of Maxwell's work

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See my answer here: Maxwell's big contribution was the notion of displacement current, which then changed the equations of electromagnetism in a way that foretold electromagnetic radiation whereby the Cartesian components of the fields all fulfilled D'Alembert's Wave equation and moreover that the wavespeed $c$ would be $c = 1/\sqrt{\mu_0\,\epsilon_0}$. The latter's ($c$, that is) surprising nearness to the experimentally known value as found by the Fizeau experiment led Maxwell to assert that light is one such electromagnetic wave.

Historians of physics widely consider that Maxwell's foretelling was first vindicated by the Hertz Spark Gap experiment.

So, without being too glib, the great J C Maxwell's main gig was the second term on the right hand side of your equation.

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Well, I am aquainted with that good. But is that all? –  Rohit Jun 12 at 10:24
    
I mean, this was the implication, but were thete any other direct hand applications of the circuital law –  Rohit Jun 12 at 10:25
    
Thats why I raised the question –  Rohit Jun 12 at 10:25
    
Well I should think what I wrote answered what you asked: if this was wonted you already, this was not apparent in your question. Applications of the modified Ampère law? EM waves ARE the main application: wireless communications, radar, radio astronomy, the grounding for the quantum description of light (in which Maxwell's equations still play a big role and are the wave equation for the lone photon) and so on and so forth. As for applications at the time, I'm not sure. I'm guessing that they would have been rather few, for the displacement current was, numerically, a subtle thing .... –  WetSavannaAnimal aka Rod Vance Jun 12 at 10:56
    
.. compared with the accuracy of their instruments. In a conductor, the ratio of displacement to conduction current is $\omega\,\epsilon/\sigma$ and this is a fantastically small number at the frequencies experimenters would have probed in Maxwell's day. To get there experimentally was Hertz's big contribution. The unmodified Ampère's law probably explained most experiments, and its inconsistency with the continuity equation was inferred theoretically as described in my other answer. –  WetSavannaAnimal aka Rod Vance Jun 12 at 10:58

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