Calculating Intensity & Distance Ratios of Two Identical/Similar Lights

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To calculate the distance ratio of two identical stars with an intensity ratio of 40 to 1, the formula E1D1^2 = E2D2^2 is appropriate, as both stars are identical. For the second scenario involving similar lights with a distance ratio of 8 to 785, the intensity ratio can be calculated using I1/D1^2 = I2/D2^2. The variables are defined as E for illumination, D for distance, and I for intensity. The discussion confirms the use of the formulas based on the characteristics of the lights involved. Understanding these relationships is crucial for accurate calculations in astrophysics and light intensity studies.
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Homework Statement



Two identical stars have intensity readings in a 40 to 1 ratio. Calculate the ratio of their distances.

Two similar lights are at distances in a ratio of 8 to 785. Calculate the ratio of intensities.


All I want to know is if I use E1D1^2=E2D2^2 or I1/D1^2=I2/D2^2. I'm quite sure I use E1D1^2=E2D2^2 for both. For the first one because they stars are the exact same, and for the second one because they are similar?
 
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you'll have to tell us what E, D, and I are.
 
E= illumination
D=distance
I=intensity
 

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