- #1
ak71
- 3
- 0
Hi all,
I have a conceptual difficulty with the idea of induction of a current in a wire due to a changing magnetic field.
Initially I was very comfortable with the idea. Upon seeing the typical setup of a square wire being rotated in a region of uniform magnetic field, I was happy to accept the outcome although I could not grasp the inner-workings of the process.
I encountered a difficult though upon seeing a different arrangement. A wire loop, being wrapped around a solenoid also has a current induced in it as the B-field inside the solenoid is increased or decreased. This pointed out a hole in my understanding. Whilst I am happy when the wire itself is bathed in B-field, the presence of a B-field only affecting the surface enclosed by the wire but not the wire itself (for the B-field outside a solenoid is near zero) confused me. I understand that that is the definition mathematically (Faraday's Law), but I can’t make the jump from the mathematics to the physics.
If someone could explain to me how a changing field in an effectively independent region of space can induce a current along a wire which itself ‘feels’ no change in field, it would be much appreciated.
Thank you very much for taking the time to read this!
I have a conceptual difficulty with the idea of induction of a current in a wire due to a changing magnetic field.
Initially I was very comfortable with the idea. Upon seeing the typical setup of a square wire being rotated in a region of uniform magnetic field, I was happy to accept the outcome although I could not grasp the inner-workings of the process.
I encountered a difficult though upon seeing a different arrangement. A wire loop, being wrapped around a solenoid also has a current induced in it as the B-field inside the solenoid is increased or decreased. This pointed out a hole in my understanding. Whilst I am happy when the wire itself is bathed in B-field, the presence of a B-field only affecting the surface enclosed by the wire but not the wire itself (for the B-field outside a solenoid is near zero) confused me. I understand that that is the definition mathematically (Faraday's Law), but I can’t make the jump from the mathematics to the physics.
If someone could explain to me how a changing field in an effectively independent region of space can induce a current along a wire which itself ‘feels’ no change in field, it would be much appreciated.
Thank you very much for taking the time to read this!