Experimental evidence of Gauss's law in electrodynamics?

In summary, the conversation discusses the relationship between Coulomb's law and Gauss's law in both electrostatic and non-static cases. It is mentioned that experimental evidence for Coulomb's law is also evidence for Gauss's law. However, in non-static cases, Coulomb's law is no longer valid and experimental evidence is needed to justify Gauss's law. The conversation also touches on the interpretation of experimental tests for Gauss's law and how it can be used to test the mass of the photon. The topic of divE=0 in pure void is also brought up, with a question about its validity and the possibility of experiments being done in a non-lab frame.
  • #1
kof9595995
679
2
In electrostatic case, Gauss's law can be derived from Columb's law, so we can regard experimental evidence for Columb's law as evidence of Gauss's law. But what about non-static case? In this case we know columb's law is no longer valid, so we need experimental evidence to justify Gauss's law, am I correct? If so, could you guys show me some of such experiments?
 
Physics news on Phys.org
  • #2
Actually, the experimental evidence is stronger for Gauss than for Coulomb.
Since both depend on the exponent 2 in Coulomb's law, testing Gauss is used as a test for that exponent. Today, most tests are interpreted as a limit on the mass of the photon, since zero mass leads to the 1/r^2. you could go to <http://pdg.lbl.gov/> [Broken] and go to the photon to see recent experimental tests.
 
Last edited by a moderator:
  • #3
Emm, true.
Actually yesterday an Italian guy came to our school and gave a seminar, discussed what can we get for EM wave if divE=0 is not necessarily true in pure void (He's a mathematician not physicist). I just didn't get the point, because i think divE=0 is well examined by experiments, and he mentioned it might not be true because we couldn't choose a reference frame relatively at rest to the EM wave(i might not hear him very clearly, but definitely something involving reference frame), but I couldn't see the logic...Do you guys understand?
Anyway that reminds me to check if there's any experiment done in a non-lab frame (relatively moving w.r.t earth)
 

1. What is Gauss's law in electrodynamics?

Gauss's law in electrodynamics is a fundamental law in electromagnetism that describes the relationship between electric fields and electric charges. It states that the electric flux through a closed surface is proportional to the total charge enclosed by that surface.

2. What is the experimental evidence for Gauss's law?

The most commonly used experimental evidence for Gauss's law in electrodynamics is the use of a Faraday cage. This is a conducting enclosure that shields its internal contents from external electric fields. When an external electric field is applied to the Faraday cage, the electric charges on its surface redistribute to create an electric field inside the cage that is equal and opposite to the external field. This demonstrates the principle of electric flux being proportional to enclosed charge.

3. How is Gauss's law experimentally tested?

Gauss's law can be experimentally tested through a variety of methods, including using a Faraday cage as mentioned above, using a parallel plate capacitor, and measuring the electric field of a point charge at different distances. These experiments all demonstrate the relationship between electric flux and enclosed charge as described by Gauss's law.

4. Can Gauss's law be applied to all situations in electrodynamics?

Yes, Gauss's law is a general principle that can be applied to all situations in electrodynamics. However, it is most commonly used in situations where there is a high degree of symmetry, such as with spherical or cylindrical objects.

5. How does Gauss's law relate to other laws in electrodynamics?

Gauss's law is closely related to other laws in electrodynamics, such as Coulomb's law and the principle of superposition. Coulomb's law describes the force between two point charges, while Gauss's law describes the overall electric field created by a distribution of charges. The principle of superposition states that the total electric field at a point is the sum of the individual electric fields from each charge, which is consistent with Gauss's law.

Similar threads

  • Electromagnetism
Replies
9
Views
3K
Replies
6
Views
864
  • Electromagnetism
Replies
4
Views
1K
  • Electromagnetism
Replies
2
Views
2K
  • Electromagnetism
Replies
14
Views
2K
  • Electromagnetism
Replies
7
Views
5K
  • Introductory Physics Homework Help
Replies
3
Views
364
  • Electromagnetism
Replies
4
Views
2K
  • Electromagnetism
Replies
1
Views
1K
  • Electromagnetism
Replies
4
Views
8K
Back
Top