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Rajni

Maxwell’s four equations describe the electric and magnetic fields arising from varying distributions of electric charges and currents, and how those fields change in time. The equations were the mathematical distillation of decades of experimental observations of the electric and magnetic effects of charges and currents. Maxwell’s own contribution is just the last term of the last equationbut realizing the necessity of that term had dramatic consequences. It made evident for the first time that varying electric and magnetic fields could feed off each otherthese fields could propagate indefinitely through space, far from the varying charges and currents where they originated. Previously the fields had been envisioned as tethered to the charges and currents giving rise to them. Maxwell’s new term (he called it the displacement current) freed them to move through space in a self-sustaining fashion, and even predicted their velocityit was the velocity of light!