Errors and Uncertainties in Paper 5 — common mistakes

In Paper 5 Question 1 (Planning), when asked to evaluate or suggest improvements to an experiment, consider sources of systematic and random errors. For example, suggesting the use of a more precise instrument (e.g., a micrometer instead of a ruler) addresses random error, while suggesting a method to check for a zero error addresses a systematic error.

Always use a 'large triangle' when calculating a gradient from a graph. This means the points you choose on the line should be separated by at least half the length of the drawn line. This minimises the uncertainty in your calculation.