Measurement and Uncertainty for IP Physics: From Sig-Figs to Spreadsheet Graphs

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04 Jul 2025, 00:00 Z

Q: What does Measurement and Uncertainty for IP Physics: From Sig-Figs to Spreadsheet Graphs cover?
A: The 2026 SEAB syllabi has a huge component of experimental skills, data handling and spreadsheet analysis.

TL;DR - New syllabus = new marks.
Quote instruments to the correct significant figures, report uncertainties as $\pm \frac{1}{2}$ least-division, and round calculated quantities to the smallest-sf raw datum.
Master absolute → fractional → percentage error conversions; propagate by addition for x / ÷, by sum of percentages for powers.
Paper 4 (practical) now explicitly allows - and tests - spreadsheet skills: gradients, intercepts, "=STDEV.S( )" and trend-lines.
Try the 20-s pendulum timing lab below; analyse your data with Sheets/Excel and you will have practised every assessed skill in one evening.

1 Why measurement & uncertainty just became high-stakes

Both O-level 6091 and A-level H2 (9478) syllabuses for 2026 list "handling experimental data, including spreadsheet processing" as an Assessment Objective worth up to 20 % of practical marks.

Specimen Paper 4 even states, "You may use a spreadsheet to process and analyse data.".

Private-tuition blogs warn that manual graph paper will be phased out, replaced by CSV uploads and Excel trend-lines.

Instrument	Least division / resolution	Raw reading rule	Example
Metre rule	\(1 \space \pu{mm}\)	\(\pm \space 0.5 \space \pu{mm}\)	\(42.0 \space \pu{cm} \pm \space 0.05 \space \pu{cm}\)
Thermometer	\(1 \space \pu{^\circ C} \)	\(\pm \space 0.5 \space \pu{^\circ C}\)	\( 23.0 \space \pu{^\circ C} \space \pm \space 0.5 \space \pu{^\circ C} \)
Digital stopwatch	\(0.01 \space \pu{s}\)	quote all decimals	\(12.37 \space \pu{s}\)

Symbol	Definition
\( \Delta x \)	Absolute uncertainty (same unit as \(x\))
\( \frac{\Delta x}{x} \)	Fractional uncertainty (no units)
\( \frac{\Delta x}{x}\times100\% \)	Percentage uncertainty \(\%\)

Trial	\(t_{20} / \pu{s}\)	\(T\( = t_{20}/20 \) / \pu{s}\)
1	31.20	1.560
…	…	…

Measurement and Uncertainty for IP Physics: From Sig-Figs to Spreadsheet Graphs

1 Why measurement & uncertainty just became high-stakes

2 Reading instruments & recording to the right sig-figs

2.1 Analogue versus digital

2.2 Sig-fig decision tree

3 Absolute, fractional & percentage uncertainty

Quick drill

4 Spreadsheet skills now examinable

5 Mini-Lab: Timing a pendulum with your phone & Sheets

5.1 Setup

5.2 Data collection

5.3 Spreadsheet crunch

6 Nine examiner-liked habits to lock in marks

7 Quick self-check

Practice Quiz

8 Further reading

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