Question

The total radiant energy per unit area, normal to the direction of incidence, received at a distance R from the centre of a star of radius r, whose outer surface radiates as a black body at a temperature TK is given by – (Where σ is Stefan's Contant)

Answer 1

Answer:

σr²T4/ R²

Explanation:

Distance = R (Given)

Radius of the star = r (Given)

Temperature = TK (Given)

According to the Stefan Boltzmann law, the power that a star radiates, whose outer surface also radiates as a black body at temperature T K is given by as -

P = σ4πr²T4

where, r is the radius of the star and σ is the Stefan's constant

The radiant power per unit area received at a distance R from the centre of a star will be described as -

S = P/ 4πR²

= σ4πr²T4 / 4πR²

= σr²T4/ R²

Thus, the temperature TK is given by σr²T4/ R².

Answer 2

Answer:

I hope this will help u....