For a point charge, the electric field is given something as the inverse of the square of the distance from it. But, that only means that as we go farther away from the point charge, the number of electric field lines PER UNIT AREA, will decrease. Therefore, if a test charge were to be placed at a far away distance, it would experience a lesser force (as there are lesser number of electric field lines per unit area) as opposed to one placed near the point charge.
The reason why I asked this question was because I was confused when I read the statement that 'electric field strength produced due to an arrangement of two infinite sheets/plates is independent of the distance from the plates.' I mean, if we consider the electric field due to ONE of the charges on the plate, then it must be dependent on distance, but it isn't.. so the only suitable reason I could think of is that along an electric field line, no matter where ON IT, the electric field strength due to that ONE line, will remain constant.
Am I wrong?