Hi, I hope this is the appropriate place and format etc. One of the questions I have to answer is this:(adsbygoogle = window.adsbygoogle || []).push({});

Use Gauss's law to obtain the field, everywhere, of charge of uniform density roe, occupying the region a<r<b, where r is the distance from the origin.

I am completely flummoxed as to what assumptions I can make..

I am assuming that since we are asked to use Gauss that I should use a spherical symmetry..

I also think that where r<a the field should be zero, but can I assume that the charge lies on the inner surface only for this region?

And where r>b should I treat the whole dstribution as a point charge?

Also, I have started trying to find E inside the a<r<b, using Q= integral(roe dV),and I end up with a term involving b^3-a^3.

If anybody could tell me if i'm on the right track of give me any pointers it would be very much appreciated.

Many thanks.

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# Finding the electric field in all regions given uniform charge occupying a<r<b

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