2022 IB Diploma Extended Essays

= 5 ∗ = 5(2 )8(.08.517±40±.400.001) = 5(2 8) .(805. 1±7 44 .±5 %0 . 5 % )

= 0.62 ± 0.03 The uncertainty for time was chosen based on reaction time, which is around 0.2 seconds. This is doubled because the timer was both started and stopped which accommodates two reaction time errors. The radius of the centripetal force apparatus has an uncertainty of ±0.001m because it was measured with a ruler. Half of the smallest increment on the ruler (0.5mm) must be doubled because there is the point where the measurement starts and where the measurement ends. Sample calculation for uncertainty of change in height: = ℎ −ℎ 2 = (0.023 + 0.001) − (0.019 − 0.001) 2 =±0.003 The uncertainty calculated for the change in height takes into account the highest and lowest value for each speed. The uncertainty caused by the ruler is also added to the highest value and subtracted from the lowest value to confirm the uncertainty is estimated to be large enough. Half of the smallest increment on the ruler is once again used twice because the initial height of the liquid was also measured.

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