Stellar luminosity Flashcards
1
Q
What is a black body?
A
An idealised object that absorbs all the electromagnetic radiation that shines onto it and when, in thermal equilibrium, emits a characteristic distribution of wavelengths at a specific temperature.
2
Q
What is Wien’s displacement law?
A
Maximum wavelength is inversely proportional to T
3
Q
What is Stefan’s law?
A
The total power radiated per unit surface area of a black body is directly proportional to the fourth power of the absolute temperature of the black body.
4
Q
What does Stefan’s law show?
A
The lumionsity of a star is directly proportional to:
- its radius squared
- surface area
- absolute temperature to the power of 4
5
Q
What is luminosity?
A
The total energy a star emits per second i.e. its power output.
