Does Gauss's Law hold true for a point charge near a sphere?

  • Context: Undergrad 
  • Thread starter Thread starter ehabmozart
  • Start date Start date
  • Tags Tags
    Gauss's law Law
Click For Summary
SUMMARY

Gauss's Law holds true for a point charge located near a sphere, specifically when analyzing a point charge at x=4 and a sphere of radius 3 cm centered at the origin. The electric field (E) is stronger at the near end of the sphere (x=3) compared to the far end (x=-3), leading to a non-zero net flux calculation. However, upon thorough mathematical analysis, it is confirmed that Gauss's Law applies, as the total flux through the surface of the sphere accounts for the density of electric field lines entering and exiting the sphere.

PREREQUISITES
  • Understanding of Gauss's Law in electrostatics
  • Familiarity with electric field concepts and field lines
  • Basic knowledge of calculus for flux calculations
  • Experience with point charge behavior in electric fields
NEXT STEPS
  • Study the mathematical derivation of Gauss's Law
  • Explore electric field calculations for various charge distributions
  • Learn about the concept of electric flux and its applications
  • Investigate the implications of Gauss's Law in non-uniform electric fields
USEFUL FOR

Students of physics, electrical engineers, and anyone interested in understanding electrostatics and the application of Gauss's Law in real-world scenarios.

ehabmozart
Messages
212
Reaction score
0
Consider a point charge on the x-axis at x=4. And a sphere with radius 3cm is kept beside the point charge centered at the origin. Consider the near end (x=3) and the far end (x=-3) ... We will find that E from the point charge is much bigger in the close end than E at the far end. So if we calculate inward and outward flux to get the net, this would not be zero since they strike the same area. Does this vilate with Gauss's Law??
 
Physics news on Phys.org
When in doubt, do the math. You will (hopefully) find that Gauss's law also applies in this case.
 
The intuition behind this case is as follows:

We think of the electric field as a bunch of arrows (field lines), with the density of them telling you the strength of the field. But they also tell you the flux through a surface, the more arrows, the more flux. If you think about the situation you came up with, how many arrows enter the sphere, and how many leave? (if you have a hard time thinking about this, "follow" a single arrow from the point charge, towards the sphere, and out to infinity. What does it do?) Does this violate gauss' law?
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 7 ·
Replies
7
Views
1K
  • · Replies 83 ·
3
Replies
83
Views
5K
  • · Replies 29 ·
Replies
29
Views
2K
  • · Replies 17 ·
Replies
17
Views
2K
  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 20 ·
Replies
20
Views
2K
  • · Replies 30 ·
2
Replies
30
Views
3K
  • · Replies 1 ·
Replies
1
Views
1K
  • · Replies 2 ·
Replies
2
Views
2K