0

I am new to it, so please help. As I know, AC current is back and forth motion of electrons, which radiates electromagnetic waves, so there is energy radiation from power line to our home. But in case of DC, if the magnetic field and electric field are static then how does energy radiate. I have searched that drift velocity of electron is slow, so DC flows at the same speed as of AC which is C. So, how does this happen if there is no radiation of DC? Please answer.

Shubham Singh
  • 1
  • Please clarify your specific problem or provide additional details to highlight exactly what you need. As it's currently written, it's hard to tell exactly what you're asking. – Community Aug 01 '23 at 05:09

1 Answers1

3

Electrons encounter a resistance as they flow through a wire. The energy used to overcome that resistance $(E=I^2R)$ is converted into heat, which is radiated in electromagnetic (infrared) radiation.

hdhondt
  • 10,898
  • But poynting vector says that whenever there is electric field and magnetic field there will be flow of energy. But what form of energy is flowing in DC? – Shubham Singh Aug 01 '23 at 07:58
  • Because DC does not produce electromagnetic waves, so what is it? – Shubham Singh Aug 01 '23 at 07:59
  • DC current produces a steady magnetic field, not an oscillating one. EM waves are only generating by oscillating fields. – hdhondt Aug 01 '23 at 23:56
  • @ShubhamSingh For a sketch of the Poynting vector in a DC circuit, see https://physics.stackexchange.com/a/301027/44126. There was a popular pair of Veritaseum videos a year or two ago which also discussed the Poynting vector in DC circuits, with plenty of internet disbelief. – rob Aug 02 '23 at 12:32