Calculating wavelengths of photons / photospheric temperatures

AI Thread Summary
The discussion focuses on calculating the wavelengths of photons that can ionize hydrogen (HI) and potassium (KI) based on their ionization potentials of 13.6 eV and 4.3 eV, respectively. The user initially applies the formula e = (hc)/λ to find the wavelengths, seeking further guidance on the next steps. There is a mention of stars having a black body spectrum, which relates to their temperature and is connected to Planck's law of black body radiation. The conversation emphasizes the need to understand how these calculations tie into the photospheric temperatures of stars that emit photons capable of ionizing these atoms. Overall, the thread highlights the relationship between photon wavelengths, ionization, and stellar temperatures.
Toad
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The ionization potentials of HI and KI are 13.6 and 4.3 ev. Calculate the wavelengths of photons that can ionize HI and KI. Calculate the photospheric temperatures of stars that peak at these wavelengths, and hence radiate plenty of photons at shorter wavelengths capable of ionizing these atoms.

First, I calculated the wavelengths using e=(hc)/lambda . I have lambda=(hc)/13.6 and lambda=(hc)/lambda . Now what do I do next? Any suggestions are welcome! Thanks in advance!
 
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Toad said:
Now what do I do next?

What kind of spectrum does a star have? How does it relate to the star's temperature?
 
SpaceTiger said:
What kind of spectrum does a star have? How does it relate to the star's temperature?
Well... it has a black body spectrum. I supposed it relates with Planck's law of black body radiation? http://en.wikipedia.org/wiki/Planck_function I'm still not exactly sure what to do.

Thanks!
 

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