Does a DC supplied wavy superconductor give off EM radiation?

binis
Messages
101
Reaction score
8
A superconductor has the shape of a uniform plane wave. If it is flowed by a direct current,
is it emitting electromagnetic radiation or not?
 
on Phys.org
When the current is initiated, a magnetic field is radiated due to the turn-on transient.

A continuous direct current maintains a stable magnetic field, being the vector sum of all the magnetic fields from all the segments of the circuit.

When the current is terminated, the radiated magnetic field will fall back to zero.
 
binis said:
If it is flowed by a direct current,
is it emitting electromagnetic radiation or not?
No. The shape of the loop is irrelevant. When it is DC there is no radiation.

binis said:
have a look to this post
Have a look at the rest of that thread. The post you mention was subsequently corrected, and since you participated there you are already aware.

What produces radiation is a changing dipole moment (or higher-order multipole). A single accelerating charge does not produce radiation because of acceleration. It produces radiation because of a changing dipole moment.

A DC current has no changing moments, so no radiation, regardless of the shape of the loop.
 
Last edited:
  • Informative
Likes   Reactions: berkeman and binis

Similar threads

  • · Replies 32 ·
2
Replies
32
Views
3K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 38 ·
2
Replies
38
Views
5K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 17 ·
Replies
17
Views
16K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 14 ·
Replies
14
Views
2K
  • · Replies 9 ·
Replies
9
Views
3K