The temperature of stars in the universe varies with the type of star and the age of the star among other things. By looking at the shape of the spectrum of light emitted by a star, we can tell something about its average surface temperature. i)If we observe a star's spectrum and find that the peak power occurs at the border between red and infrared light, what is the approximate surface temperature of the star

  T = 3.6 10³ K

Explanation:

A good way to calculate the surface temperature of a star is to approximate it as a black body, and use Wien's displacement law.

            λ T = 2,898 10⁻³

In this case they tell us that the light from the star is between red (700nm) and light infrared (2500nm) suppose that the radiation is

            λ = 800 nm (near infrared)

             T = 2,898 10⁻³ /λ

             T = 2,898 10⁻³/ (800 10⁻⁹)

             T = 3.6 10³ K

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