EF intensity

[computerages]

heya every1~!

 

My question is that why the intensity of electric fields is same at any point in teh field...??... Let's say an electron moves closer to the positive side of the field, would not the force of attraction be more on that electron than the one that is not as much closer to + side?...

[timo]

My question is that why the intensity of electric fields is same at any point in teh field...??...

In general, it isn´t. You probably have a specific field configuration in mind or mistook the results of a specific field configuration for being true in general.

[swansont]

You're thinking of a parallel plate capacitor, right? As Atheist stated, it's not true in general.

 

The ideal parallel place capacitor always looks the same, no matter where you are, since it is infinite in extent, or approximately so for the length of a side >> separation distance. When you get closer to one plate, more of the charges give you a lateral force, which cancels out, and this balances the fact that you are closer to them. Fewer charges give you a large force in the direction of the field. It all balances to give you a constant field.

[abskebabs]

Dude, the electric field strength only remains constant between two charged plates of arbitrarily long length. An example would be a capacitor with 2 plates at different electric potentials. The electric field strength is simply the gradient or rate of change of the electric potential with increasing displacement displacement from plate to plate.

 

Otherwise, as Atheist correctly said. this is not the case and the electric field strength is inversely proportional to the displacement squared between two point charges(for simplicity's sake). The charged plate example is actually a simpler reiteration of this in a way, under different circumstances.

 

I have not quoted any maths, but I suggest you look it up if you want to improve your understanding. A good website to start would be hyperphysics. Just search for it in google.

 

Hope that helped:-)

[abskebabs]

damn swansont beat me to it!

[timo]

Dude' date=' the electric field strength only remains constant between two charged plates of arbitrarily long length. [...']

Otherwise, as Atheist correctly said, this is not the case [...]

I know it´s a bit nitpicking (don´t get me wrong, it was a nice post of yours) but since you´re semi-quoting me with things I didn´t say let me add this minor correction: The "between two charged plates"-scenario is not the only one in which the intensity of the electric field remains constant.

[abskebabs]

I know it´s a bit nitpicking (don´t get me wrong, it was a nice post of yours) but since you´re semi-quoting me with things I didn´t say let me add this minor correction: The "between two charged plates"-scenario is not the only one in which the intensity of the electric field remains constant.

I don't consider it nitpicking at all;) , and I'm sorry if I misinterpreted you. In fact I confess, I do not know any other cases where electric field strength remains constant, and so I enquire; Could you tell me some? In my A level physics course I have only covered the 2 charge plates example and the spheres/point charges examples. I am interested in learning more and it seems evident to me by now there is much more to learn:-)

[insane_alien]

a single infinite planar plate would have a uniform electric field i believe

[timo]

I do not know any other cases where electric field strength remains constant, and so I enquire; Could you tell me some?

The inside of a uniformly charged hollow sphere would come to my mind, first. Admittedly, it might be not what the OP had in mind as the field is constant zero. But strictly speaking it qualifies as constant.

[abskebabs]

Would an arbitrarily long cylindrical or spherical plate produce a similiar field?

[abskebabs]

The inside of a uniformly charged hollow sphere would come to my mind, first. Admittedly, it might be not what the OP had in mind as the field is constant zero. But strictly speaking it qualifies as constant.

lol, now u beat me to my post:-p . I guess I spend too long pondering when I'm about to post.

[abskebabs]

Would an arbitrarily long cylindrical or spherical plate produce a similiar field?

I should have added from the inside of the spherical or cylindircal plate plate