Two point charges +q and -q are held fixed at `(-a,0)` and `(a,0)` respectively of a x-y coordinate system then

Options

A. The electric field E at all points on the x-axis has the same direction
B. No work has to be done in bringing a test charge from `oo` to the origin
C. Electric field at all point on y-axis is parallel to x-axis
D. The dipole moment is 2 qd along the -ve x-axis

Answer

A

Explanation

In figure `(-d, 0)` to `(d, 0)` on x-axis the direction of `vec(E)` in +ve x-axis and left side of `(-d, 0)` the direction in -ve x-axis, but on y axis, at any point the net electric field along the x-aixs.