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emr564
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Why is the Qenclosed zero if there's a charge inside the shell?
A solid conducting sphere of radius a is placed inside a conducting shell which has an inner radius b and an outer radius c. There is a charge q1 on the sphere and a charge q2 on the shell.
Find the electric field at point P, where the distance from the center O to P is d, such that b<d<c.
There's a diagram which shows:
radius of solid conducting sphere = a
inner radius of conducting shell = b
outer radius of conducting shell = c
O is the center from which all radii are measured.
Flux = EA = Qencl/εnaught
A = 4∏r^2
E = Qenclosed/ (εnaught*4∏d^2)
I have the solution already, which is E=0, but I don't understand why the charge enclosed is 0. I understand that the charge on the shell spreads to the outer surface of that shell since it's a conductor, so that charge wouldn't be enclosed in the Gaussian sphere with radius d. I don't get why the charge on the solid sphere doesn't count, though.
In the problem before it, the question asked for the electric field at a point in between the solid sphere and the spherical shell, and the answer was kq1/d^2, which means that in the space between, the enclosed charge is q1.
Homework Statement
A solid conducting sphere of radius a is placed inside a conducting shell which has an inner radius b and an outer radius c. There is a charge q1 on the sphere and a charge q2 on the shell.
Find the electric field at point P, where the distance from the center O to P is d, such that b<d<c.
There's a diagram which shows:
radius of solid conducting sphere = a
inner radius of conducting shell = b
outer radius of conducting shell = c
O is the center from which all radii are measured.
Homework Equations
Flux = EA = Qencl/εnaught
A = 4∏r^2
The Attempt at a Solution
E = Qenclosed/ (εnaught*4∏d^2)
I have the solution already, which is E=0, but I don't understand why the charge enclosed is 0. I understand that the charge on the shell spreads to the outer surface of that shell since it's a conductor, so that charge wouldn't be enclosed in the Gaussian sphere with radius d. I don't get why the charge on the solid sphere doesn't count, though.
In the problem before it, the question asked for the electric field at a point in between the solid sphere and the spherical shell, and the answer was kq1/d^2, which means that in the space between, the enclosed charge is q1.
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