Electric Field and Potential due to Induced Charges

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gracy
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Homework Statement


If there is an uncharged metal spherical body and a charge q outside it .Find Electric field due to induced charges.

Homework Equations


##E##=##\frac{Kq}{r^2}##

The Attempt at a Solution


If there is an uncharged metal spherical body and a charge q outside it then there will be induced charges on it's surface like this
UNCHARGED.png

Electric field inside the body should be zero.Electric field due to +q would be ##E##=##\frac{Kq}{r^2}## there fore Electric field due to induced charges should be equal in magnitude to that of ##E##=##\frac{Kq}{r^2}## and opposite in direction.But my question is this electric field due to induced charges is due to +q induced or -q induced?
 
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gracy said:

Homework Statement


If there is an uncharged metal spherical body and a charge q outside it .Find Electric field due to induced charges.

Homework Equations


##E##=##\frac{Kq}{r^2}##

The Attempt at a Solution


If there is an uncharged metal spherical body and a charge q outside it then there will be induced charges on it's surface like this
View attachment 93590
Electric field inside the body should be zero.Electric field due to +q would be ##E##=##\frac{Kq}{r^2}## there fore Electric field due to induced charges should be equal in magnitude to that of ##E##=##\frac{Kq}{r^2}## and opposite in direction.But my question is this electric field due to induced charges is due to +q induced or -q induced?
What does the question ask you to do? "Find Electric field due to induced charges." That must include all of the charges mentioned with the exception of the given charge, +q.
 
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SammyS said:
That must include all of the charges mentioned with the exception of the given charge, +q.
And what if we are asked to find electric field due to +q induced?
 
gracy said:
And what if we are ask to find electric field due to +q induced?
The induced charge is distributed over the surface with varying density. It would be a very involved process to find the electric field due to +qinduced by itself or the electric field due to -qinduced by itself.
 
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