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I was reading about the power radiated by an oscillating electric dipole. It then said that monopoles don't radiate.

But a monopole is just a charge, right? And an accelerated charge radiates EM waves. Can someone please explain.

Qmechanic
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Matrix23
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1 Answers1

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Dipoles can radiate because a time changing electric dipole moment does not violate the conservation of charge (you can think of the two opposite charges rapidly changing places with time). However, for the value of an electric monopole (a single charge) to change with time without there being any other charge in the region, conservation of charge would have to be violated; Which is impossible.

Edit: I don't think that the author of what you're reading means an accelerating charge; just like us not considering accelerating dipoles when we are talking about dipole radiation.

Sahand Tabatabaei
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