If the intensity of electromagnetic radiation (I) is equal to the power emitted (P) divided by the area of the sphere (4pi(r^2)) that it radiates, why is the inverse-square law 1/(r^2) instead of P/(4pi(r^2))? Shouldn't the radiation emitted propagate isotropically in all directions (sphere) instead of anisotropically (cube)? I apologize for the notation; I don't know how to write in latex. Thank you.(adsbygoogle = window.adsbygoogle || []).push({});

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# Inverse-square law

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