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Question
Equipotentials at a great distance from a collection of charges whose total sum is not zero are approximately.
Options
spheres
planes
paraboloids
ellipsoids
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Solution
spheres
Explanation:
The collection of charges, whose total sum is not zero, with regard to great distance can be considered as a single-point charge. The equipotential surfaces due to a point charge are spherical.
Important point:
- The electric potential due to point charge q is given by V = q/4πε0r
- It means electric potential due to point charge is same for all equidistant points. The locus of these equidistant points, which are at the same potential, form spherical surface.
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