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  1. The inconsistency of Ampere's law can be removed by adding __________ to it.

  2. A.
    displacement current density alone.
    B.
    conduction current density alone.
    C.
    displacement and conduction current densities.
    D.
    none of these

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    Answer : Option A

    Explanation :

    The ampere's law is given as

    ∇.H = J

    Taking divergence on both sides

    ∇.(∇xH) = ∇.J

    i.e., ∇.(∇xH) = ∇.J = 0

    divergence of curl is always zero

    But ∇.J = -rv ... continuity equation.

    Hence the inconsistency. It can be removed as follows

    Let ∇ x H = J + G where G is some unknown quality.

    Then ∇.(∇ x H) = ∇.(J x G) = 0

    i.e. ∇.J + ∇.G = 0

    i.e. ∇.J = -∇.G

    or ∇.G = (-rv)

    i.e. ∇.G = rv ...... Gauss's law in point form

    Differentiating on both sides.

    ∇.D = rv

    Comparing (i) and (ii), G = D

    Thus ∇ x H = J + D

    Where J is conduction current density and D is displacement current density which is added to remove the inconsistency of Ampere's law.


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