- #1

Zahid Iftikhar

- 116

- 24

I have read one excellent explanation on the question I am posting again, at another thread on PF, because I am not able to completely understand the concept. Please spare some more time.

I need help to understand how an electric field due to an infinite sheet of charge can be uniform where ever you experience it. I know the electric fields die down inverse squarely by increasing the distance. I understand all the charges keep the field perpendicular and straight from the plane of the sheet. But it makes me confused to believe that if a charge is placed at 1cm distance and then moved to 4cm distance along the same electric field line, there will be same force. In this way if a charge is taken to infinity, again there will be same field intensity. The equation, I know , for electric field intensity is independent of distance from the sheet of charge but physically it seems incorrect.

As far this explanation goes that components of E parallel to the plane of sheet cancel out and those perpendicular add up to produce uniform field does not convince me. Here is the reason.

For a point near the sheet, the supporting components of E will have greater strength, so they will produce strong field near the sheet. Whereas for a point away from the sheet of charge, these components should have individually weak values and thus when add should produce weak field.

Please help.

High regards

Zahid Iftikhar