What is the Electric Field Inside and Outside of a Sphere?

AI Thread Summary
The discussion centers on understanding the electric field inside and outside a sphere, particularly in relation to Griffith's electrodynamics problems. It highlights confusion regarding the electric field's behavior in two specific problems: one indicating a non-zero field inside the sphere and the other stating that the total enclosed charge is zero, leading to a zero field. Clarification is provided that a zero total charge within a Gaussian surface does not imply a zero electric field, but rather that the net electric flux is zero. The conversation emphasizes the importance of context when determining whether the enclosed charge is zero or not. Understanding these concepts is crucial for grasping the fundamentals of electric fields in spherical geometries.
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hi guys, i have been following griffith's book on electrodynamics and i m stuck with probably one of the basic concepts on electric field. i did not understand what would be the electric field, 1) inside and 2)outside of a sphere with radius R ?

also there are two problems which deals with spheres, the first one be prob 2.8 says there should be some electric field inside but prob 2.15 says the total enclosed charge inside is zero, hence field zero. maybe i m not so clear on the idea of electric field, but on which context we can say the inside charge is zero or not.
someone please make me clear on this.
regards
 
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Compare problem 2.8 with 2.15 - either there is a different method being used or there is some other important difference.

Note: zero total charge enclosed in a Gaussian surface does not mean zero field - it means there is net zero flux going through the surface. i.e. as many flux lines leave as enter.
 
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