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A person measures the depth of a well by measuring the time interval between dropping a stone and receiving the sound of impact with the bottom of the well. The error in his measurement of time is δ T = 0.01 seconds and he measures the depth of the well to be L = 20 meters. Take the acceleration due to gravity g = 10 ms –2 and the velocity of sound is 300 ms –1 . Then the fractional error in the measurement, δ L/L, is closest to
- 5%
- 3%
- 0.2%
- 1%
Correct answer: 1%
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