I have tried for a while finding an answer to this question. Similar ones have been explained earlier by using Gauss law. However I am wondering about the physical change happening to the conductor in this case:
As far as Ive understood, there are no electric field INSIDE the conducting material if a charge (displayed as a blue B) is inside a cavity of a conducting material. But my question is simply then, how can one have a negative surface on the cavity surface area and a positive surface on the outside area of the conductor.
I have seen some people mention free charges in the conducting material neutralizing the electric field on the inside of the material, but how can one neutralize the surface charges WITHOUT also removing the electric field on the outside of the conduction material?