Physics: AM Radio Station Emits Photons/sec at 1000-kHz

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yakin
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Physics: An 84-kW AM radio station broadcasts at 1000-kHz. How many photons are emitted each second by the transmitting antenna? (h=6.626E-32 Js)
 
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yakin said:
Physics: An 84-kW AM radio station broadcasts at 1000-kHz. How many photons are emitted each second by the transmitting antenna? (h=6.626E-32 Js)

Energy of a single photon with frequency $$\nu$$ is:

$$E_{\nu}=h \nu$$

where $$h$$ Plank's constant.

So for our 1000 kHz signal the energy of a single photon is:

$$E_{\nu}=h \nu= 6.626\times 10^{-32} \times 1000 \times 1000= 6.626\times 10^{-28}$$ J

The radio station is emitting $$E_s=8.4\times 10^4$$ Joules per second, so the number of photons emited per second is:

$$N=\frac{E_s}{E_{\nu}}$$

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