Luminosity vs Power: Stars & W

[Mafia]

If one star is say 10 times more luminous than another star would that mean it would have 10 times more power as in W? And would that relationship continue with increased luminousity as in a star 1000 times more luminous would have 1000 times more power?

 

[phyzguy]

Basically, yes. Luminosity has units of energy per time, and is typically measured in ergs/sec(CGS) or joules/sec(MKS), with joules per second being the same as watts.

 

[Dotini]

As a layman, the way I read the H-R diagram, white dwarfs have less luminosity and less absolute visual magnitude than most main sequence stars, yet can have higher surface temperature, higher frequency color index (B-V), and higher surface current density. But perhaps this has nothing to do with power?

Respectfully submitted,
Steve

 

[phyzguy]

It does have to do with power. The luminosity is the power of the radiation that the stars emit. Since a star is roughly a blackbody, the total luminosity of a star is $$L =4\pi r^2 * \sigma T^4$$
where sigma is the Stefan-Boltzmann constant. White dwarfs emit a lot of radiation per square cm of surface area because their temperature is high, but their total luminosity is low because their radius is so small.

 

[pmacias]

I can confirm that there is a direct relationship between luminosity and power in stars. Luminosity is a measure of the total amount of energy a star emits per unit time, while power is the rate at which energy is transferred or transformed. Therefore, a star that is 10 times more luminous than another star would also have 10 times more power. This relationship would continue with increased luminosity, meaning a star that is 1000 times more luminous would have 1000 times more power.

However, it is important to note that luminosity and power are not the only factors that determine the overall behavior and characteristics of a star. Other factors such as mass, temperature, and evolutionary stage also play a significant role. Therefore, while a star with higher luminosity may have a higher power output, it may not necessarily be more massive or hotter than a star with lower luminosity.

In conclusion, the relationship between luminosity and power in stars is directly proportional, but it is not the only factor that determines a star's overall behavior and characteristics. Further research and analysis are needed to fully understand the complexities of stars and their energy outputs.