The accuracy in the measurement of time for 20 oscillations of a pendulum for the following measurements, t 1 = 39.6   s , t 2 = 39 . 9   s and t 3 = 39 .5  s , is

Step-by-step solution

Given, t 1 = 39.6 s t 2 = 39.9 s t 3 = 39.5 s Least count of measuring instrument = 0.1 s [As measurements have only one decimal place] Precision in the measurement = Least count of the measuring instrument = 0.1 s Mean value of time for 20 oscillations t = t 1 + t 2 + t 3 3 = 3 9 . 6 + 3 9 . 9 + 3 9 . 5 3 = 3 9 . 7 s Absolute errors in the measurements Δ t 1 = t - t 1 = 3 9 . 7 - 3 9 . 6 = 0 . 1 s Δ t 2 = t - t 2 = 3 9 . 7 - 3 9 . 9 = - 0 . 2 s Δ t 3 = t - t 3 = 3 9 . 7 - 3 9 . 5 = 0 . 2 s Mean absolute error = Δ