Stars: A star has absolute luminosity equal to that of the sun, which is 1.5 × 10⁸ km from the earth, but this star is 32.6 light-years away from the earth. By what factor will it appear dimmer than the sun? (1 ly = 9.461 × 10¹⁵ m) A) 2.4 × 10^-9 B) 2.4 × 10^-11 C) 2.4 × 10^-13 D) 2.4 × 10^-15 E) 2.4 × 10^-17

Question

Quizplus · Accepted Answer

The apparent brightness of a star is inversely proportional to the square of its distance. The distance to the star is 32.6 light-years, which is much greater than the distance to the sun. Calculating the factor by which the star appears dimmer involves converting the distance to meters and using the inverse square law.

Stars: a Star Has Absolute Luminosity Equal to That of the Sun