If these stars are both 500 light-years away from earth, how will their apparent
ID: 1551856 • Letter: I
Question
If these stars are both 500 light-years away from earth, how will their apparent brightness compare? (Express your answer as an integer) Ba/Bb= ?And
How will the apparent brightness of these stars compare if Star A is twice as far away as Star B? Express your answer using two significant figures) ? Ba/Bb= ? If these stars are both 500 light-years away from earth, how will their apparent brightness compare? (Express your answer as an integer) Ba/Bb= ?
And
How will the apparent brightness of these stars compare if Star A is twice as far away as Star B? Express your answer using two significant figures) ? Ba/Bb= ?
And
How will the apparent brightness of these stars compare if Star A is twice as far away as Star B? Express your answer using two significant figures) ? Ba/Bb= ?
Explanation / Answer
Brightness is inversely proportional to d^2 where d is the distance
B= L/(4*pi*d^2)
a) when distance of both the stars are 500 light years
Ba/Bb= (L1/L2)* (d2/d1)^2
Ba/Bb= (3)* (500/500)^2
= 3
Ba = 3*Bb
Answer: Brightness of A is 3 times that of B
b)
a) when distance of both the stars are 500 light years
Ba/Bb= (L1/L2)* (d2/d1)^2
Ba/Bb= (3)* (1/2)^2
= 3/4
Ba = 3/4*Bb
Answer: Brightness of A is 0.75 times that of B