Electric Field at Radius r from Concentric Conducting Spherical Shells?

[Chronos000]

Homework Statement

The question I'm struggling with is to find the electric field at radius r from the centre of two conducting spherical shells of radius a and b (b>a), and with charge +Q and -Q.

Specifically I am not sure if there is no electric field at r>b as if you use gauss' law, the total charge within the gaussian surface is 0.

 

[G01]

Specifically I am not sure if there is no electric field at r>b as if you use gauss' law, the total charge within the gaussian surface is 0.

This is correct. The total enclosed charge is 0, so the flux through any Gaussian surface with r>b will be 0.

 

[Chronos000]

thanks for confirming