Question 221: Units , Dimensions and Error Analysis

Question

A student measures the time period of 100 oscillations of a simple pendulum four times. The data set is 90 s, 91 s, 95 s and 92 s. If the minimum division in the measuring clock is 1 s, then the reported mean time should be :

Accepted Answer

Here t
1
= 90 s, t
2
= 91 s, t
3
= 95 s, t
4
= 92 s
Mean(t) = ${{{t_1} + {t_2} + {t_3} + {t_4}} \over 4}$
= ${{90 + 91 + 95 + 92} \over 4}$ = 92 s
Now mean deviation
= ${{2 + 1 + 3 + 0} \over 4}$ = 1.5 s
Since least count of clock is one second, so reported mean time
= (92 $ \pm $ 2) s

Answer

92 $ \pm $ 1.8 s

Answer

92 $ \pm $ 3 s

Answer

92 $ \pm $ 2 s

Answer

92 $ \pm $ 5.0 s

Units , Dimensions and Error Analysis

A student measures the time period of 100 oscillations of a simple pendulum four times. The data set is 90 s, 91 s, 95 s and 92 s. If the minimum division in the measuring clock is 1 s, then the reported mean time should be :

Choose the correct answer: