As you know, the word current means flow. An electric current (conduction current) is caused by flow of electrons.
But while considering the continuity of electric current in a circuit with a capacitor as a component, it becomes difficult to explain the continuity as there is no physical medium between the plates of the capacitor for the electrons to flow. But the effect (magnetic) can be felt in between the plates too. This is explained by the Maxwells equations, the Ampere Maxwell law, also called the modified Ampere’s circuital law.
The original form of Ampere’s circuital law is insufficient to explain the continuity of current in the above case. But according to Maxwell, a time varying electric flux can also produce effects similar to that of conduction current. This “current” (though there is no flow of charges) is termed as displacement current.
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