Field Strength and Field Lines

Most recent answer: 06/16/2017

Q:
it is given in my book that electric field intensity is directly proportional to the no. of field lines passing through specific area. Electric field lines are imagimary and there would be infinite field lines passing through any area (as in electric field, every point would let field lines pass through it and there are infinite points in any specific area we can choose. In this way how can we say that more are the no. of field lines passing more is the electric field intensity?
- Harsh (age 17)
Hathras
A:

You make an excellent point. The field lines are just a pictorial way of describing the field. The claim that the field strength is given by the density of the field lines can only work on a distance scale large compared to the spacing between the lines, so then it includes all the points in that region, not just those on the lines. In order to picture fields on a small scale, you have to use lots of lines.

Mike W.


(published on 06/16/2017)