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JEE PHYSICS MCQ: UNITS & MEASUREMENTS

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A physicist performs an experiment and takes 200 readings. He repeats the same experiment and now takes 800 readings. By doing so the probable error

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Correct option: D

Is reduced by a factor of 1/4

Option D (Is reduced by a factor of 1/4) is correct because the error is inversely proportional to the square root of the number of readings. Since the number of readings is multiplied by 4, the error is divided by the square root of 4, which is 2. The variance is reduced by a factor of 4.

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