Creating hypotheses, identifying risks, and measuring and recording data accurately are valuable skills when conducting experiments.
Part ofBiology (Single Science)Practical skills
Try to be more precise in your measuring. Use an instrument with a smaller resolution, and read it to the smallest reading possible.
Ruler A will give a more precise reading and will reduce the uncertainty in your result.
An uncertainty of 1 mm in 25 mm is 4 %.
An uncertainty of 1 cm in 2.5 cm is 40 %. This is ten times bigger.
\({\%{\text{~uncertainty in reading}}}=\frac{\text{instrument resolution}\times 100\%}{\text{reading taken}}\)
The resolution is the smallest division on the instrument.
What is the uncertainty of a resolution of 0.01 ml in 5.52 ml?
(0.01 ÷ 5.52) × 100 % = 0.18 %
What is the uncertainty of a resolution of 0.5 ml in 5.5 ml?
(0.5 ÷ 5.5) × 100 % = 9.1 %