Electric field intensity with a charge decreasing over time

AI Thread Summary
The discussion revolves around finding the electric field intensity inside and outside a lossy dielectric sphere with an initial uniform charge distribution that decreases over time. The user proposes that the relationship σ∇E = dp/dt, where p represents volume density, is key to deriving the electric field expression. They mention using spherical coordinates for the divergence of E and integrating over r but express difficulty in incorporating the time variable t into their calculations. Another participant suggests that a more structured approach using a specific template might yield better results. The conversation emphasizes the need for clarity and completeness in formulating the problem to facilitate assistance.
ForTheGreater
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So a lossy dielectric sphere gets an initial charge distribution evenly across the sphere.

Find an expression for E inside and outside the sphere for all t.



I figured that σ∇E=dp/dt
p being volume denity.

So I apply spherical coordinates to the div of E and integrate over r to get an expression for E. But I need to do something with the dp/dt since I want t in the expression.
 
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Hello For,

Perhaps you have a better chance to get some assistance if you formulate a bit more completely using the template. Lossy ? ## \sigma ## <--> dp/dt ?
 
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