Electric field outside a gaussian surface

Click For Summary
In a uniform electric field E, a Gaussian surface that encloses zero charge will have a net electric field of zero at its surface, according to Gauss's law. The law states that the electric field is only influenced by the charge enclosed within the surface, not by external charges. Electric field lines from external charges that enter the Gaussian surface will also exit, resulting in no net flux. Therefore, the electric field inside or at the surface of the Gaussian surface does not reflect the presence of external charges. Understanding this principle clarifies the relationship between enclosed charge and electric field behavior.
Ibraheem
Messages
51
Reaction score
2
Hello

If we have a gaussian surface that is placed in a uniform electric field E and encloses 0 charge, what would the E-field at the gaussian surface be? I have assumed the gaussian surface to be cubic surface, and then I have found from Gauss's law that the electric field is zero at the surface even though there is a constant electric field. Can someone please clarify what I am not getting here. Is the electric field in the closed surface integral of Gauss's law is only related to the enclosed charge or is related to outer charges.

Thanks
 
Physics news on Phys.org
It is only related to the enclosed charge. Think about it this way. The field lines from unenclosed charge that enter the Gaussian surface will exit it eventually, producing no net flux.
 
So gauss's law provides information related to the enclosed charge, but nothing about electric field and charge magnitude outside the gaussian surface.
 
I'm working through something and want to make sure I understand the physics. In a system with three wave components at 120° phase separation, the total energy calculation depends on how we treat them: If coherent (add amplitudes first, then square): E = (A₁ + A₂ + A₃)² = 0 If independent (square each, then add): E = A₁² + A₂² + A₃² = 3/2 = constant In three-phase electrical systems, we treat the phases as independent — total power is sum of individual powers. In light interference...

Similar threads

  • · Replies 2 ·
Replies
2
Views
1K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 83 ·
3
Replies
83
Views
5K
  • · Replies 8 ·
Replies
8
Views
5K
  • · Replies 103 ·
4
Replies
103
Views
8K
Replies
3
Views
3K
  • · Replies 30 ·
2
Replies
30
Views
3K
  • · Replies 14 ·
Replies
14
Views
2K