Question

A sphere of radius a that is made of a conductive dielectric (: σο ande Ere) is centered about the ongin The sphere is charged at t 0 s with a uniform charge density given by pu(t 0) po for all R s a, where Po is a positive constant (a) Starting from the continuity equation, V J prove that the charge density within the dielectric sphere varies according to pu(t)-pe Tro. (3 points) (b) If it is known that at t-: 0 s the conduction current density within the sphere is given by J(R, t O) edo RaR, determine the expression for the conduction current density for t 2 0 s. Hint: Assume this current density is only a function of R. [3 points] (c) Find the ratio of the magnitude of the conduction current density relative to the magnitude of the displace- ment current density for t 2 0s. 3 points)

Answer 1

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