Star a and star b have different apparent brightnesses but identical luminosities. star a is 10 light years away from earth and appears 36 times brighter than star b. how far away is star b?

intensity of a star is inversely depends on the square of the distance from the star

we can say it is given as

here we know that

also we know that

now we will have

so other star is at distance 60 Light years

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