Data, graphs and experimental reasoning
IB Physics Paper 1B Toolkit
Work through measurements, choose a graph, test a model and explain what the evidence supports.
Aligned to the course first assessed in 2025. Official sources checked 15 September 2026. Independent resource; not endorsed by IB.
What the official documents establish
Paper 1B is the data-response part of Paper 1, worth 20 marks at both SL and HL. The combined 1A/1B session is 90 minutes at SL and 120 minutes at HL; there is no separate fixed 1B time allocation in the guide. Calculators are permitted and the physics data booklet is provided.
The course develops measurement, data processing, graphical analysis and evidence-based evaluation across topics. Our tools are a study-support mapping of those skills, not a guarantee of which tasks an examination will contain. The website is for preparation, not an approved examination calculator.
Official physics guide: assessment details · Official 2025 specimen papers and markschemes
Readings and uncertainty
Instrument readings & zero error
Correct a zero offset and estimate reading uncertainty using a stated resolution convention or supplied instrument uncertainty.
Open calculatorRepeated measurements & timing
Calculate mean, range, half-range uncertainty and uncertainty per cycle, with an explicit instrument floor and comparison to SEM.
Open calculatorPercentage uncertainty
Convert absolute uncertainty into percentage uncertainty. See the formula, substituted values and a correctly rounded measurement.
Open calculatorAbsolute uncertainty
Find absolute uncertainty from a measured value and percentage uncertainty, with full working and matched decimal-place rounding.
Open calculatorUncertainty propagation
Propagate uncertainties for sums, differences, products, quotients and powers using school-lab rules, with all working shown.
Open calculatorSignificant figures
Round decimal or scientific-notation numbers to 1–15 significant figures. Understand leading zeros, trailing zeros and halfway rounding.
Open calculatorGraphs and processed data
Error bars & acceptable lines
Plot x and y uncertainty bars, test a candidate line against every rectangle, and find maximum/minimum gradients and intercept bounds.
Open calculatorLinearization & log plots
Transform both axes with squares, roots, reciprocals or logarithms. Propagate uncertainties, fit a line and export processed data.
Open calculatorGraph gradient, area & prediction
Find segment gradients, linearly interpolate or extrapolate, and estimate signed area with trapezoids. See each interval and its working.
Open calculatorGradient uncertainty
Find gradient uncertainty from maximum and minimum acceptable slopes, plus percentage uncertainty and a rounded best-gradient result.
Open calculatorLinear regression
Fit a straight line to two-column data. Calculate slope, intercept, R², Pearson r and coefficient standard errors with a graph and working.
Open calculatorStandard deviation & error
Calculate mean, population and sample standard deviation, and standard error from a list of measurements, with formulas and full working.
Open calculatorUnits, models and conclusions
SI units & dimensional checks
Convert simple and compound physics units, expand derived SI units, and detect incompatible dimensions with transparent scale factors.
Open calculatorPhysical constants from gradients
Turn a graph gradient into g, spring constant, resistivity or an exponential time scale, with first-order propagated uncertainty.
Open calculatorAgreement within uncertainty
Compare two measurement intervals or a result with an accepted value. Check overlap and see the numerical gap with a careful conclusion.
Open calculatorPercentage error & difference
Calculate percentage error against an accepted value or percentage difference between two values. Compare definitions and see the working.
Open calculatorA useful route through a data question
- Read the context, axis multipliers, units and stated uncertainty convention.
- Identify the model, independent variable, dependent variable and controls.
- Transform data only when the equation justifies it. Label the processed units.
- Use a broad gradient triangle and examine every uncertainty bar. Interpret the intercept.
- Carry uncertainties through the calculation, then round the final answer.
- Write a conclusion tied to numerical evidence, assumptions and specific limitations.
What still needs your judgment
Choosing apparatus, explaining an anomaly, drawing a free-body diagram and defending an experimental improvement cannot be reduced to a reliable automatic score. The workbook gives prompts and original examples for these skills. It does not generate a mark or certify that a method is valid.