SOLUTION: the intensity of illumination from a source of light varies inversely as the square of the distance from the source. (a) at what distance from a source of light will the intensity
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-> SOLUTION: the intensity of illumination from a source of light varies inversely as the square of the distance from the source. (a) at what distance from a source of light will the intensity
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Question 1109450: the intensity of illumination from a source of light varies inversely as the square of the distance from the source. (a) at what distance from a source of light will the intensity of illumination be half as great as it is at a distance of 6 inches? (b) how much closer to a source of light must an object be moved so that the intensity of illumination which it receives will be 44 per cent more than that which it receives at a distance of 3 feet? Answer by rothauserc(4718) (Show Source):
You can put this solution on YOUR website! (a)intensity of illumination from a source of light at 6 inches is 1/6^2 = 1/36
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half the illumination is (1/36)/2 = 1/72
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square root of 72 = 8.49 inches
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(b) at three feet, illumination is 1/9
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(1/9) + 0.44 * (1/9) = 0.16
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square root(0.16) = 0.4 feet
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3 feet - 0.4 feet = 2.6 feet closer
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