Share
Star A and star B appear equally bright in the sky. Star A is twice as far away from Earth as star B. How do the luminosities of stars A and
Question
Lost your password? Please enter your email address. You will receive a link and will create a new password via email.
Answers ( )
Answer:
The answer to the question is
The luminosity of stars A is four times that of star B
Explanation:
Flux (F) produced by a source of light is directly proportional to the brightness or Luminosity (L), and varies inversely to its distance d, that is [tex]F \alpha \frac{L}{d^2}[/tex]
Therefore if the two stars present the same flux then we have
[tex]\frac{L_1}{d_1^2} = \frac{L_2}{(2d_1)^2}[/tex] then crossing out like terms gives [tex]\frac{L_1}{1} = \frac{L_2}{2^2}[/tex] or 4·L₁ = L₂
The luminosity of star A is 4 times the that of star B