(radiation) monpoles vs. dipoles

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Griffiths explains in Chapter 11 that an electric monopole, such as a stationary point charge, does not radiate energy. In contrast, a point charge with an electric dipole moment radiates power, calculated using the formula P = μ₀ q² a²/(6πc), where a(t) is the acceleration of the dipole moment. The term "monopole" refers to any charge distribution that produces a spherically symmetric electric field outside a defined region. This distinction highlights the differences in radiation behavior between static and dynamic charge configurations. Understanding these concepts is crucial for grasping the principles of electromagnetic radiation.
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In the chapter on radiation (Chapter 11), Griffiths notes that an electric monopole does not radiate, but also that a point charge of electric dipole moment \mathbf{p} (t) = q \mathbf{d} (t) (where \mathbf{d} (t) is the instantaneous coordinate of the charge with respect to a fixed origin ) radiates with power
P = \mu_0 q^2 a^2/(6 \pi c), where \mathbf{a}(t) = \ddot{\mathbf{p}} (t). By "monopole," does he simply mean a point charge that doesn't move?
 
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That would be one case. Any distribution of charge which gives a spherically symmetric field outside of a certain region is an electric monopole.
 
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