Question

In: Physics

Two stars are the same size. One star has a temperature of 50,000 K, the other...

Two stars are the same size. One star has a temperature of 50,000 K, the other has a temperature of 5,000K. Compared to the cooler star, how many times more luminous should the hotter star be? Which star will appear bluer?

Expert Solution

We know that two things describe the luminosity of a star 1. Radius 2. Surface temperature. As both stars are of the same size so here luminosity only depends upon surface temperature.

So here

as radius is same.

For star hotter star

for cooler star

So hotter star will be 10000 times more luminous as compared to the cooler star.

Also according to Wein's displacement law

or star with higher temperature will posses lower wavelength. So hotter star will appear blue.

genius_generous answered 2 years ago

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