The diagrams below show regions of equipotentials.
A positive charge is moved from A to B in each diagram.
Maximum work is required to move q in figure (c).
In all the four cases the work done is the same.
Minimum work is required to move q in figure (a).
Maximum work is required to move q in figure (b).
As we learnt in
Work done in moving a charge -
Always be zero in equipotential surface.
-
work done is given as
In all the four cases the potential difference from A to B is same
In all the four cases the work done is same.