What this topic covers
Measurements and their errors has 3 subtopics:
- Use of SI units and their prefixes
- Limitation of physical measurements
- Estimation of physical quantities
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A Level AQA Physics · Topic 1 of 13
Measurements and their errors – A Level AQA Physics revision notes
Choose a subtopic. Measurements and their errors covers Use of SI units and their prefixes, Limitation of physical measurements, and Estimation of physical quantities in A Level AQA Physics. 6 lessons in 3 subtopics.
Revise Measurements and their errors for A Level AQA Physics, including Use of SI units and their prefixes and Limitation of physical measurements.
6
Lessons
3
Subtopics
Measurements and their errors lessons by subtopic
6 lessons, grouped by subtopic.
Use of SI units and their prefixes
- Introduction to SI Units: Explore fundamental and derived SI units, including mass, length, time, amount of substance, temperature and electric current. Understand the base units and how derived units are created. Note: Candela is excluded and students don't need to recall definitions of fundamental quantities.
- SI Prefixes and Unit Conversions: Learn about SI prefixes and how to use them. Practice converting between different units using these prefixes. Includes use of prefixes: T, G, M, k, c, m, μ, n, p, f. Learn how to convert between different units of the same quantity, eg J and eV, J and kW h.
Limitation of physical measurements
- Errors, Precision, and Accuracy: Explore random and systematic errors, and define precision, repeatability, reproducibility, resolution, and accuracy in measurements.
- Uncertainties: Absolute, Fractional and Percentage: Learn about uncertainty, and how to calculate absolute, fractional, and percentage uncertainties. Also, understand how to represent uncertainty in a final answer.
- Uncertainties on Graphs: Represent uncertainty in a data point on a graph using error bars and determine the uncertainties in the gradient and intercept of a straight-line graph.
Estimation of physical quantities
- Orders of Magnitude and Estimation: Learn about orders of magnitude and how to estimate approximate values of physical quantities.
More in this course
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Frequently asked questions
What is Measurements and their errors?
Measurements and their errors covers Use of SI units and their prefixes, Limitation of physical measurements, and Estimation of physical quantities in A Level AQA Physics. 6 lessons in 3 subtopics.
How do you calculate percentage uncertainty?
Divide the absolute uncertainty by the measured value to get the fractional uncertainty, then multiply by 100. The Uncertainties: Absolute, Fractional and Percentage notes cover this in full.
What is an electronvolt?
An electronvolt is the kinetic energy gained by an electron when it is accelerated through a potential difference of exactly 1 volt. The SI Prefixes and Unit Conversions notes cover this in full.
How do you draw a line of best fit?
A line of best fit is a straight line that passes as close as possible to all the points, with roughly equal numbers of points on each side of the line. The Uncertainties on Graphs notes cover this in full.
What is the difference between repeatability and reproducibility?
Repeatability is the precision when the same operator uses the same equipment and method over a short time. The Errors, Precision, and Accuracy notes cover this in full.
How do you show the joule is kg m² s⁻²?
Start from the defining equation W = F × d. The Introduction to SI Units notes cover this in full.
What is a newton in SI base units?
A newton is kg m s⁻² in base units. The Introduction to SI Units notes cover this in full.
How do you convert joules to electronvolts?
Joules are converted to electronvolts by dividing by 1.6 × 10⁻¹⁹. The SI Prefixes and Unit Conversions notes cover this in full.
What is the resolution of an instrument?
Resolution is the smallest change in a quantity that an instrument can detect and display. The Errors, Precision, and Accuracy notes cover this in full.