Question

4. A certain very bright star has an effective surface temperature of 20,000 K.
(a) Assuming that it radiates as a blackbody, what is the wavelength at which u( λ ) is maximum?
(b) In what part of the electromagnetic spectrum does the maximum lie?

Answer 1

\[\lambda _ \max = (2.898*10^-3)/T\] This is the equation I used to get that max. So am I suppose to use this lambda inside here?
\[u(\lambda)=(8\pi hc \lambda ^{-5} )/(e^{hc/\lambda kT}-1) \]

Answer 2

No, lambda max is just the wavelength of maximum emission. You're not plugging in anything for it, just plug in your temperature...

Answer 3

And then you'll get a wavelength that may be in the visible range, or in the x-ray range, or gamma ray, etc.

Answer 4

Okay thanks.