The Peak of the intensity versus wavelength plot (Planck curve) ???

Question

Does that phrase change the fact that

Higher temp = shorter wavelength


Explain whether the wavelength at which we would find the peak of the intensity versus wavelength plot (Planck curve) for a star with a surface temperature of 8100K is at a longer or shorter wavelength than that of a star with a surface temperature of 6600K.

Answer 1

No it does not. Higher temperatures have their peak intensities at bluer colors (shorter wavelengths, longer frequencies).

Answer 2

No, it doesn't change that fact. In fact it's fully consistent with it, and could hardly be otherwise, as the following argument shows.

Think of it this way:

TEMPERATURE is a measure of ENERGY (the classical connection is E = nkT), as is FREQUENCY via Planck's inspired relationship:

E = h nu, where nu is the (circular) frequency of the radiation.

(As you may know, the shape of the Planck curve versus wavelength peaks at kT being a certain multiple of h nu.)

This means that the peak frequency nu scales with T. However, (lambda)*(nu) = c, where lambda is the wavelength.

Therefore T scales INVERSELY with wavelength, i.e.

Higher temp ==> shorter wavelength.

Live long and prosper.