Regarding ' The Electric field inside a non conducting shell '

[Uday]

Homework Statement

There is a Uniformly charged Non conducting Spherical shell along with a point charge external to the shell . they make up an isolated system . Find the electric field inside the shell .

Homework Equations

The Attempt at a Solution

Actually using superposition principle we obtain that the field is actually non zero . But in order to calculate the electric field inside the shell if i use gauss law by considering a gaussian surface inside the shell ... there will be no charge enclosed in it so by gauss law the flux is zero . since in that case ∫E.da = E∫da which is equal to zero . Since ∫da is non zero E must be zero ...
I guess there is some fault with this but I am unable to find it out . So please can u help me .
And thanks for sparing ur valuable time to read this .

 

[haruspex]

∫E.da = E∫da

That will not be true in general. Is anything known about the shape of the shell?

 

[Uday]

That will not be true in general. Is anything known about the shape of the shell?

Im sorry that's a spherical shell
and i have edited my question .

 

[Tanya Sharma]

Hello Uday

Actually using superposition principle we obtain that the field is actually non zero . But in order to calculate the electric field inside the shell if i use gauss law by considering a gaussian surface inside the shell ... there will be no charge enclosed in it so by gauss law the flux is zero . since in that case ∫E.da = E∫da which is equal to zero . Since ∫da is non zero E must be zero ...
I guess there is some fault with this but I am unable to find it out . So please can u help me .
And thanks for sparing ur valuable time to read this .

I think the problem lies in concluding that if the flux across the gaussian spherical surface is zero ,then the electric field is zero .

What is your reasoning behind moving E out of the integral ∫E.ds ?

 

[Uday]

Ya ... that's ryt E isn't constant ...

 

[haruspex]

Im sorry that's a spherical shell
and i have edited my question .

OK, so forget the point charge for the moment. What field does a uniformly charged spherical shell generate inside itself?
Hint: when considering a Gaussian shell placed concentrically inside it, think about the symmetry.