Does Higher Luminosity Mean Higher Power in Stars?

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SUMMARY

Higher luminosity in stars directly correlates to higher power output, measured in watts. Luminosity, defined as energy per time, is quantified in units such as ergs/sec (CGS) or joules/sec (MKS), with joules per second equivalent to watts. The relationship holds true across varying luminosities; for instance, a star that is 1000 times more luminous will emit 1000 times more power. The discussion also highlights that while white dwarfs exhibit high surface temperatures and radiation per unit area, their overall luminosity remains low due to their smaller radii.

PREREQUISITES
  • Understanding of stellar luminosity and its measurement units (ergs/sec, joules/sec)
  • Familiarity with the Stefan-Boltzmann Law and its application in astrophysics
  • Knowledge of the Hertzsprung-Russell (H-R) diagram and its significance in stellar classification
  • Basic concepts of blackbody radiation and surface temperature in stars
NEXT STEPS
  • Study the Stefan-Boltzmann Law in detail to understand its implications for stellar luminosity
  • Explore the Hertzsprung-Russell diagram to analyze the relationship between luminosity, temperature, and stellar evolution
  • Investigate the characteristics of white dwarfs and their role in the lifecycle of stars
  • Learn about blackbody radiation and its relevance to astrophysical phenomena
USEFUL FOR

Astronomers, astrophysics students, and anyone interested in understanding the relationship between stellar luminosity and power output.

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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?
 
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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.
 
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
 
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.
 

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