# Photon energy of black-body

1. Aug 13, 2012

### Orion78

I have calculate that the mean approximate photon energy of a black-body spectrum which is emitted by an object at a temperature of 1 million K is 300eV. Can somebody confirm me that? My second doubt is: the wavelength at which this spectrum reaches a peak corresponds to a "longer" or to a "shorter" wavelength than that of the black-body spectrum emitted by the sun?
Many thanks

2. Aug 13, 2012

### Drakkith

Staff Emeritus
What do your calculations show for the Sun?

3. Aug 14, 2012

### Orion78

I did not do any calculation about the sun but think that the spectrum of solar radiation is close to that of a black body with a temperature of circa 5,800 K and so the mean approximate photon energy is 1.74eV. If that so, are the wavelength at which this spectrum of the object at at a temperature of 1 million K that reaches a peak corresponds to a much shorter wavelength than that of the black-body spectrum emitted by the sun?

4. Aug 14, 2012

### Staff: Mentor

300eV-photons have a shorter wavelength than 1.74eV-photons.
The numbers are in a region where I would expect them, but I did not calculate them.

5. Aug 14, 2012

### Drakkith

Staff Emeritus
Yes, the peak is a much shorter wavelength than the Sun emits. Do you know much about EM radiation and black body radiation?

6. Aug 14, 2012

### Orion78

Thanks. yes, now I have all the info I needed.