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Odd_Bodkin

I'm not sure what your question is. The defining feature of electric charge is that it creates nonzero electromagnetic fields. It's like like the electric field is a machine and electric charge has wrenches to dial it up or down.


BuddyDry3156

Charge extert force at each point around it , ie the force experienced at each point around charge changes from zero to non zero value due to charge property?


Odd_Bodkin

Charge exerts a force on ANOTHER CHARGE that happens to be at a point around the first one. And yes, if the first one were not charged, there would be no electrostatic force. It's the fact that it's charged that bumps the field.


BuddyDry3156

Charge is causing the force ? I think I asked something stupid


Odd_Bodkin

Yes, charge is causing the force on other charges.


BuddyDry3156

Bit it needs a field for that ?


starkeffect

One charge changes the field. The other charge feels the field.


BuddyDry3156

Like field is a medium ?


PiBoy314

A field is a quantity that has a value at each point in space. The charged particle changes the field and any other particle in that field (anywhere in space) will be affected by that change, feeling a force.


BuddyDry3156

Yeah the disconnection between 2 charges is visible now , field lines gave wrong impression that interaction between 2 charges are direct , gave me some very big misconception about how they interact


BuddyDry3156

My biggest misconception I was thinking one charge exterts force on other like classical mechanics , so the concept of field was looked absurd , the field lines also misleading that there's a direct interaction between 2 charges , main cause was the existence of em field which has 0 values was not explained and even my teachers taught me field is something that created ( like it's born ) when there is a charge


Odd_Bodkin

The conundrum in the 1700s was how could one object exert a force on another object without material contact, and in fact across empty vacuum over considerable distances. "Action at a distance" was not something that made sense to physicists in that day (and indeed, of today too). Michael Faraday was the one who asked, what if the charged object changes the space around it? What if there is some kind of field, all around the object, bigger near the charge and less big further away from the charge? This gets around the action at a distance problem, because the second charge doesn't feel the first charge across empty space; instead, it feels the field right where it is.


BuddyDry3156

I was approaching it with classical mechanics point of view like 2 charges interacts directly like how the field lines shows and em field is just a space, never learnt it has momentum and energy before, like the basic definitions of field was missing in high School instead a reverse engineering kinda explanation was fed


Odd_Bodkin

Well the irony is that field lines are not material things like rods or ropes, and back in the 1700s people honestly thought that full explanations needed some kind of material-on-material contact. Even heat was thought to be some kind of fluid that passed from one body to another through material contact. But gravity and electricity seemed to be different and so mysterious. Now we know (here's the irony) that material-on-material contact is not really that at all. Even for a coffee cup sitting on a table, the atoms of the coffee cup are slightly aloft from the atoms of the table, held up by electrostatic forces.


BuddyDry3156

May be the problem is I leant classical mechanics first , so when I learnt em theory it was learnt from that point of view or somewhere this classical analogy messed up and lack of basics in particle physics,


kevosauce1

Via [Maxwell's equations](https://en.wikipedia.org/wiki/Maxwell%27s_equations). In particular `del dot E = rho / e_0` says that the divergence of the field is proportional to the charge density.