Three charges each`+q`, are placed at the corners of an isosceles triangle `ABC` of sides `BC` and `AC, 2a, D` and `E` are the mid-points of `BC` and `CA`. The work done in taking a charge `Q` from `D` to `E` is

Options

A. `(eqQ)/(8piepsilon_(0)a)`
B. `(qQ)/(4piepsilon_(0)a)`
C. zero
D. `(3qQ)/(4piepsilon_(0)a)`

Answer

C

Explanation

Here, `AC = BC`
As `D` and `E` are the third mid points of `BC` and `CA`, the potential of these points should be equal.
`V_(D)=V_(E )=V`
The work done in talking a charge `Q` from `D` to `E`
`W= Q[V_(E )-V_(D)]=Q[V-V]=0`