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Question
Why is there no work done in moving a charge from one point to another on an equipotential surface?
Solution
On an equipotential surface, the potential remains constant and thus potential difference (ΔV) is zero. The work done on a charge q is given as
W = qΔV
Now, as ΔV = 0
We conclude that W = 0
So, the work done in moving a charge from one point to another on an equipotential surface is zero.
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Equipotentials at a great distance from a collection of charges whose total sum is not zero are approximately.
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