a. Influence of a conducting plane on the distribution of an electric field originated from a positive charge +q, located at distance y0. y=0 within the plate.
b. The same electric distribution is predicted by the mirror image method between the charge q and an imaginary charge –q with location y=-y0, x=0. The real lines of the electric field are shown by solid lines and the imaginary lines of the electricfield are shown by dotted lines.