Answer:
Explanation:
The Stefan-Boltzmann law establishes that a black body (an ideal body that absorbs or emits all the radiation that incides on it) "<em>emits thermal radiation with a total hemispheric emissive power proportional to the fourth power of its temperature":
</em>
(1)
Where:
is the energy radiated by a blackbody radiator per second, per unit area (in Watts). Knowing
is the Stefan-Boltzmann's constant.
is the Surface of the body
is the effective temperature of the body (its surface absolute temperature) <u>in Kelvin
.</u>
However, <u>there is no ideal black body</u> (ideal radiator) although the radiation of stars like our Sun is quite close.
Therefore, for the case of the star Rigel, we will use the <u>Stefan-Boltzmann law for real radiator bodies:
</u>
(2)
Where is the star's emissivity
Now, firstly we need to find , in the case of Rigel, its surface area can be approximated to a sphere, so:
(3)
(4)
Knowing this value, let's substitute it in (2):
(5)
(6) This is the total energy radiated by Rigel each second.