Electricity and Magnetism question.

[hhhmortal]

Hello I have these two questions on electricity and magnetism which I don't understand very well these are:

(Q1) If a closed surface encloses no charge, and electric field lines cross the surface.

(Q2) Under what conditions can coloumb's law be used to find the electric field strength.


Thanks a lot

 

[WiFO215]

Coulombs law completes Electrostatics. If you understand what it implies mathematically, you're done with statics. But it does not hold for mobile charges. Under static conditions you can use it to find E.

 

[Phrak]

A single function axiomatic system? Two, as charges are static. Other than what should be considered as implicit, such as Euclidian space + time, and Newtonian mechanics, I can think of only one other axiom; that is continuity of charge.