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Question
The electrostatic potential on the surface of a charged conducting sphere is 100V. Two statements are made in this regard S1 at any point inside the sphere, electric intensity is zero. S2 at any point inside the sphere, the electrostatic potential is 100 V. Which of the following is a correct statement?
Options
S1 is true but S2 is false.
Both S1 and S2 are false.
S1 is true, S2 is also true and S1 is the cause of S2.
S1 is true, S2 is also true but the statements are independent.
Solution
S1 is true, S2 is also true and S1 is the cause of S2.
Explanation:
We know, the electric field intensity E and electric potential V are related E = dV/dr
If electric field intensity E = 0, then dV/dr = 0. It means E = 0 inside the charged conducting sphere causes uniform potential inside the sphere. Hence uniform electrostatic potential 100 V will be at any point inside the sphere.
Important points:
- The electric field zero does not necessary imply that electric potential is zero. E.g., the electric field intensity at any point inside the charged spherical shell is zero but there may exist non-zero electric potential.
- If two charged particles of the same magnitude but opposite signs are placed, the electric potential at the midpoint will be zero but the electric field is not equal to zero.
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