Time for 20 oscil

Given:

Time measurement for 20 oscillations of a pendulum

t₁=39.6s

t₂=39.9s

t₃=39.5s

Since, all the measurements have a maximum of on decimal place, the lease count of the instrument used to measure the time is 0.1s.

Since precision in measurement is equal to the least count of the instrument, therefore

Now the mean value of time period of the pendulum for 20 oscillations:

Now mean time period for one oscillation:

Now accounting for the precision in measuring time for one oscillation we have the measured mean time period

Now the accuracy in measurement is given by the maximum observed error from the measured value, which is