Class 12th Physics 2017 Set2 Delhi Board Paper Solution
How does Ampere-Maxwell law explain the flow of current through a capacitor, when it is being charged by a battery? Write the expression for the displacement current in terms of the rate of change of electric flux .
When we charge a capacitor with the help of a cell, current flows all through the circuit except the part of circuit which lies between two plates of capacitor. There is no current found in that gap. But it was found that an electric field exist inside the plates therefore, indicating existance of magnetic field which leads to inconsistency in the Ampere’s circuital law. Account this problem concept of displacement current was introduced by Maxwell.
According to Ampere’s Maxwell law, displacement current is arise due to the changing electric field which in turn creates magnetic field between the plates.It can be shown as:
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