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Is 89MHZ station emitting photons of 89MHZ frequency? (I mean $\nu$ in $E=h\nu$).

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Oneat, yes, and I understood what you meant "I mean this one". ;-) You meant that it's the frequency $\nu$ (nu) that appears in the formula $E=h\nu$ for the photon energy, as opposed to $\omega$ that appears in $E=\hbar\omega$ and that differs by a factor of $2\pi$.

Whenever you hear "$\mbox{Hz}$" or any multiple of it, it means that the frequency is defined in the same convention as the frequency in $E=h\nu=hf$, without the slashed $\hbar$ (hbar). If someone wanted to express the angular frequency $\omega=2\pi\nu$, he would have to write the unit as $\mbox{s}^{-1}$ instead of $\mbox{Hz}$. (Or often radian per second is used, rad s^-1, which is unambiguous)

Dimensionally, $\mbox{Hz}$ is the same thing as $\mbox{s}^{-1}$. However, people deliberately use both units so that the inverse second is reserved for the angular frequency $\omega$ and the Hertz is reserved for the old-fashioned frequency $\nu$.

$\nu=89 \mbox{MHz}$ is the same thing as $\omega=5.6\times 10^{8} \mbox{s}^{-1}$.(though 5.6 x10^8 rad/sec is less ambiguous)

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