The sun as a blackbody:

a. the sun is a 6000-k blackbody. at what characteristic wavelength does it radiate?

b. at what characteristic wavelength does a blackbody at room temperature radiate?

c. how much power per unit area is the sun radiating?

Explanation:

(a) Using Wien's displacement law which states that the temperature and the wavelength of the blackbody radiation are inversely proportional.

So,

λmax= b/T

Where,  

λmax is the peak of wavelength

b is the Wien's displacement constant having value as

T is the Absolute Temperature in Kelvins = 6000 K

So,  

λmax= b/T  = = 4.8333 × 10⁻⁷ m

It lies in the visible region.

(b) Using Wien's displacement law:

λmax= b/T

So,  

λmax= b/T  = = 9.73154 × 10⁻⁶ m

This wavelength corresponds to infrared region.

(c) The expression for power per unit area by using Stefan–Boltzmann law is:

Power per unit area = εσT⁴

Where, ε = 1 for blackbody

σ is Stefan–Boltzmann constant, having value as

Thus,

P =

c- cold periods in earth's history during which glaciers covered much of the surface.

explanation: