SOLUTION: The intensity (I) of a light source is inversely proportional to the square of the distance (d) from the source. If the intensity is 8 lumens at a distance of 6 m, what is the inte

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: The intensity (I) of a light source is inversely proportional to the square of the distance (d) from the source. If the intensity is 8 lumens at a distance of 6 m, what is the inte      Log On


   

Question 315745: The intensity (I) of a light source is inversely proportional to the square of the distance (d) from the source. If the intensity is 8 lumens at a distance of 6 m, what is the intensity when the distance is 4 m?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
The intensity (I) of a light source is inversely proportional to the square of the distance (d) from the source.
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I = k/d^2
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If the intensity is 8 lumens at a distance of 6 m,
Find "k":
8 = k/6^2
k = 8*36 = 288
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Equation for Your Problem:
I = 288/d^2
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what is the intensity when the distance is 4 m?
I = 288/4^2
I = 18 lumens
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Cheers,
Stan H.
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