(a) d^2 = k/I
(b) I1 d1^2 = I2 d2^2
d2^2/d1^2 = I1/I2
The intensity of the light from an object varies inversely with the square of the distance. In other words, I = k over d^2
a. Solve the equation to find d in terms of I.
b. Two stars give off the same amount of light. However, from Earth their intensities differ. Let I sub 1 and I sub 2 be their intensities and let d1 and d2 be their respective distances from Earth. What is the ratio of d sub 2 to d sub 1?
c. If one star appears 9 times as intense as the other, how much closer is it to Earth?
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