Find potential inside spherical shell

AI Thread Summary
The discussion focuses on calculating the electric potential at point A, located R/2 from the center of a conducting sphere with charge Q, influenced by an external charge q placed at a distance of 2R. The initial approach incorrectly sums the potentials from the sphere and charge q, suggesting V = kQ/R and V = 2kq/5R. However, it is noted that the sphere is an equipotential region, and the influence of charge q complicates the distribution. The correct method involves using the concept of image charges to account for the non-symmetrical charge distribution. Ultimately, the potential at the center due to the sphere remains kQ/R, while the potential from charge q must also be considered to find the total potential at point A.
utkarshakash
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Homework Statement


A conducting sphere of radius R has a charge Q. A particle carrying a charge q is placed a distance 2R from the sphere. Find the potential at point A located a distance R/2 from the center of the sphere on the line connecting the center of the sphere and particle q. Note that the charge distribution of the sphere is not symmetrical due to the influence of particle q


The Attempt at a Solution



The potential at point A will be equal to sum of potential due to sphere and charge 'q'.
Due to sphere, V= kQ/R
and due to charge, V= 2kq/5R

But this is not the correct answer.
 

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utkarshakash said:
The potential at point A will be equal to sum of potential due to sphere and charge 'q'.
Due to sphere, V= kQ/R
and due to charge, V= 2kq/5R

But this is not the correct answer.

The item in red is not correct .
 
utkarshakash said:

Homework Statement


A conducting sphere of radius R has a charge Q. A particle carrying a charge q is placed a distance 2R from the sphere. Find the potential at point A located a distance R/2 from the center of the sphere on the line connecting the center of the sphere and particle q. Note that the charge distribution of the sphere is not symmetrical due to the influence of particle q


The Attempt at a Solution



The potential at point A will be equal to sum of potential due to sphere and charge 'q'.
Due to sphere, V= kQ/R
and due to charge, V= 2kq/5R

But this is not the correct answer.

Hint:the whole sphere is an equipotential region.
 
utkarshakash said:

Homework Statement


A conducting sphere of radius R has a charge Q. A particle carrying a charge q is placed a distance 2R from the sphere. Find the potential at point A located a distance R/2 from the center of the sphere on the line connecting the center of the sphere and particle q. Note that the charge distribution of the sphere is not symmetrical due to the influence of particle q .


The Attempt at a Solution



The potential at point A will be equal to sum of potential due to sphere and charge 'q'.
Due to sphere, V= kQ/R
and due to charge, V= 2kq/5R

But this is not the correct answer.
The reason that V= kQ/R is incorrect for the sphere is highlighted in RED above.

Use the concept of image charges .
 
projjal said:
Hint:the whole sphere is an equipotential region.

Will the potential at centre be equal to kQ/R due to sphere?
 
utkarshakash said:
Will the potential at centre be equal to kQ/R due to sphere?

Yeah.

You also know the potential at centre due to charge q and wid that you get the answer.
 
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