In an electric field region, the electric potential varies along the x-axis as shown in the graph. The `x` components of the electirc field in the regions for the intervals `PQ` and `QR` as market in the garph, in `N//C`, are respectively:

Options

A. `5.0` along negative `x`-direction and `20.0` along positive x-direction
B. `5.0` along positive `x`-direction and `20.0` along negative `x`-direction
C. `5.0` along negative `x`-direction and `20.0` along negative `x`-direction
D. `5.0` along positive `x`-direction and `20.0` along positive x-direction

Answer

D

Explanation

`E_(PQ) = - (dV_(PQ))/(X_(PQ)) = - ((V_(Q) - V_(P)))/(X_(PQ)) = (-(10 - 5))/(1.0) = 5N//C`
and `E_(QR) = - ((-10 - 0))/(0.5) = 20N//C`