The sketch below shows cross-sections of equipotential surface between two charged conductors that are shown in solid black. Some points one the euquipotential surface near the conductors are marked as A, B, C ………. The arrangement lies in air. `["Take " in_(0)=8.85xx10^(-12) C^(2)//N m^(2)]`

How much work is required to slowly move a `-1 mu C` charge from E to D?

Options

A. `2xx10^(-5) J`
B. `-2xx10^(-5) J`
C. `4xx10^(-5) J`
D. `-4xx10^(-5) J`

Answer

D

Explanation

Here `V_(DE)=V_(D)-V_(E)=20-(-20)=40V`
Work done`=qV_(DE)`
`=-1xx10^(-6)xx40`
`=-4xx10^(-5) J`