4
$\begingroup$

This question already has an answer here:

According to Maxell's Electromagnetic Wave theory, an accelerating charged particle radiates energy and this is one of the arguments due to which the Rutherford model of an atom(In which Rutherford compares electrons revolving around the nucleus to planets revolving around the sun) was rejected.


My question is that even though planets have zero nett charge they are still composed of electrically charged species and if the planet is under constant acceleration due to its revolution, aren't the constituent electrically charged particles of the planet under acceleration? Why don't we see planets emitting photons and spiralling into the sun?

$\endgroup$

marked as duplicate by Yashas, Diracology, Qmechanic Feb 28 '17 at 11:47

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • 4
    $\begingroup$ Possible duplicate of Why do planets not radiate EM waves in their orbits? $\endgroup$ – Lelouch Feb 28 '17 at 11:29
  • 1
    $\begingroup$ the question has an answer here : physics.stackexchange.com/q/267268 $\endgroup$ – Lelouch Feb 28 '17 at 11:30
  • $\begingroup$ Fact: Planets radiate gravitational waves (unless they are perfect spheres). $\endgroup$ – Yashas Feb 28 '17 at 11:34
  • $\begingroup$ @YashasSamaga That is correct but Why don't they radiate electromagnetic waves due to the fact that they are under continuous acceleration? $\endgroup$ – Aniansh Feb 28 '17 at 11:38
1
$\begingroup$

EDIT: Just noticed the duplicates, apologies: Why don't planets emit EM waves ?

A few considerations:.

  1. What's the velocity of the Earth compared to the velocity of an electron in an electric field?

  2. As you say, the Earth has a net charge of zero, but if you take the charged particles (as a tiny, tiny percentage of the mass of the Earth), how much momentum do they carry away, in a spherically symmetrical direction, (so total momemtum loss is neglible).

$\endgroup$
  • $\begingroup$ Shouldn't the mass of the charged particles be a little more than half the mass of a neutral body(mass of electrons + mass of protons)? $\endgroup$ – Aniansh Feb 28 '17 at 11:35

Not the answer you're looking for? Browse other questions tagged or ask your own question.