What causes the electric field in a changing magnetic field?

  • Thread starter Thread starter pardesi
  • Start date Start date
AI Thread Summary
A large loop enclosing an area can induce an electromotive force (emf) when a changing magnetic field is present, even if the field is localized. Faraday's law supports this phenomenon, suggesting that the loop can effectively integrate the magnetic field over a distance. The analogy of a gas cylinder bursting illustrates how the loop collects the effects of the magnetic field, regardless of its strength or distance. The discussion raises questions about the source of the electric field produced by this process. Understanding these principles is crucial in grasping electromagnetic induction.
pardesi
Messages
337
Reaction score
0
well consider a loop L a very big one i.e enclosing a large area. say in some small part of the lopp say approxiamtely at it's centre there is a magnetic field(only in that small area the field is present) which keeps changing with time.so is an inducede mf developed in the loop
yes farady's law says so.but doesn't that seem so anti-intutive.it's like a gas cylinder bursts in arctic and the fire is in antarctic:-p
 
Physics news on Phys.org
The field isn't present in a small area, it spreads out for ever, getting weaker.
But the big ring of wire is able to collect the field over a large distance and 'add' all the weak bits of field together.

It's like a gas cylinder bursts inside a bank vault and you pick up all the pieces of shrapnel easily or a gas cylinder bursts in an aircraft hanger, you still pick up all the same pieces of the cyclinder - you just have to walk further to do it.
 
hmmm. nice correlation
so what is that that produces the field(electric)
 
Hello! Let's say I have a cavity resonant at 10 GHz with a Q factor of 1000. Given the Lorentzian shape of the cavity, I can also drive the cavity at, say 100 MHz. Of course the response will be very very weak, but non-zero given that the Loretzian shape never really reaches zero. I am trying to understand how are the magnetic and electric field distributions of the field at 100 MHz relative to the ones at 10 GHz? In particular, if inside the cavity I have some structure, such as 2 plates...
Back
Top