Notes
Reading material from teachers and learners: theory, worked examples and questions that make you think. Some notes are made with AI, and they always say so.
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Experimental SkillsHigh School (11–12)
Experiments with Circuits, Lenses and Diodes: Quick Revision
A brief note on Experiments with Circuits, Lenses and Diodes: Ohm's law, the metre bridge, the potentiometer, a galvanometer made into meters, the diode, and the lens, slab and prism, with formulas, practice and questions to check yourself.
Principles Related to Practical ChemistryHigh School (11–12)
Titrations and Preparations: Quick Revision
A brief note on titrations and preparations. Standard solutions, indicators, the permanganate titrations of oxalic acid and Mohr's salt, and six preparations with their yields. It has a worked example, practice, a program and questions.
ProbabilityHigh School (11–12)
Dice Sums, Matching and Geometric Probability: Quick Revision
A brief note on dice sums, matching and geometric probability: the ways to get a total, repeated trials seen as counting, birthdays and derangements, probability on a line and in a square, and checking an answer by simulation.
Structural Organisation in AnimalsHigh School (11–12)
The Cockroach, with the Earthworm and the Frog: Quick Revision
A brief note on The Cockroach, with the Earthworm and the Frog: the body, the gut, the open blood system, the air tubes, the nerves and the life cycle of the cockroach, with the usual slips and questions to check yourself.
Trigonometry and Waves by ComputerHigh School (11–12)
Waves by Computer: Adding and Fitting: Quick Revision
A brief note on Waves by Computer: the travelling wave in numpy, adding waves for beats and standing waves, harmonics of a string, the FFT, sampling and aliasing, and fitting a sine with curve_fit. With practice, a program and questions.
Learning from SamplesHigh School (9–10)
Testing an Idea with Simulation: Quick Revision
A brief note on testing an idea: the null and alternative ideas, the p-value by simulation and by counting, shuffling tests, significance, the two kinds of error and many tests. With practice, a program and questions to check yourself.
Experimental SkillsHigh School (11–12)
Experiments with Wires, Liquids, Heat and Sound: Quick Revision
A brief note on Experiments with Wires, Liquids, Heat and Sound: Searle's method, capillary rise, Stokes' law, mixtures, cooling and the resonance tube, with the formulas, the graphs, practice and questions to check yourself.
Principles Related to Practical ChemistryHigh School (11–12)
Inorganic Qualitative Analysis: Quick Revision
A brief note on inorganic qualitative analysis. The tests for ten anions, the group scheme and tests for twelve cations, and why the group reagents work. It has a worked example, practice, a program and questions.
ProbabilityHigh School (11–12)
Probability by Counting: Quick Revision
A brief note on probability by counting: the classical definition and the axioms, the complement and at least one, odds, the addition theorem for two and three events, and the counting tools for cards, committees and arrangements.
Structural Organisation in AnimalsHigh School (11–12)
Muscular and Neural Tissue, Organs and Organ Systems: Quick Revision
A brief note on Muscular and Neural Tissue, Organs and Organ Systems: the three muscles, the neuron and the neuroglia, the levels of organisation and the organ systems, with the usual slips and questions to check yourself.
Trigonometry and Waves by ComputerHigh School (11–12)
Angles, the Unit Circle and Trigonometric Graphs: Quick Revision
A brief note on Angles, the Unit Circle and Trigonometric Graphs: degrees and radians, the unit circle, the graphs of sine, cosine and tangent, and checking identities with numpy. With a worked example, practice, a program and questions.
Learning from SamplesHigh School (9–10)
Confidence Intervals for Proportions and Means: Quick Revision
A brief note on confidence intervals: the point estimate, the margin of error, the interval for a proportion and its conditions, the sample size, the meaning of the level and the interval for a mean. With practice, a program and questions to check yourself.
Experimental SkillsHigh School (11–12)
Measuring Instruments, Errors and the Best-Fit Line: Quick Revision
A brief note on Measuring Instruments, Errors and the Best-Fit Line: the vernier calipers and the screw gauge, significant figures, the rules for errors, the pendulum graph and the least-squares line, with practice and questions to check yourself.
Principles Related to Practical ChemistryHigh School (11–12)
Detecting Elements and Groups in Organic Compounds: Quick Revision
A brief note on detecting elements and groups in organic compounds. The copper(II) oxide test, the sodium fusion test for nitrogen, sulphur and halogens, and the tests for each functional group, with a worked example, practice, a program and questions to check yourself.
ProbabilityHigh School (11–12)
Sample Spaces and Events: Quick Revision
A brief note on sample spaces and events: the list of all outcomes, the types of event, the algebra of events and De Morgan's laws, with a worked example, practice, a program and questions to check yourself.
Structural Organisation in AnimalsHigh School (11–12)
Epithelial and Connective Tissues: Quick Revision
A brief note on Epithelial and Connective Tissues: the kinds of epithelium, the cell junctions, the glands, and the loose, dense and special connective tissues, with the usual slips and questions to check yourself.
Biology by ComputerHigh School (11–12)
Genetics by Computer: Quick Revision
A brief note on Genetics by Computer: gametes as letters, sorted genotypes, Punnett squares with loops and Counter, two genes with itertools.product and the 9:3:3:1 ratio, the test cross, and simulated crosses with random.choice. With practice, a program and questions.
Learning from SamplesHigh School (9–10)
Sampling Variability and Sample Size: Quick Revision
A brief note on sampling variability: parameters and statistics, the sampling distribution, the standard error of a mean and of a share, and the square root rule. With practice, a program and questions to check yourself.
Electromagnetic WavesHigh School (11–12)
Energy, Intensity and Momentum of Electromagnetic Waves: Quick Revision
A brief note on Energy, Intensity and Momentum of Electromagnetic Waves. It covers energy density, intensity, field strengths from a power, radiation pressure and the usual calculations, with a worked example and questions to check yourself.
States of MatterHigh School (11–12)
Vapour Pressure, Surface Tension and Viscosity: Quick Revision
A brief note on Vapour Pressure, Surface Tension and Viscosity: boiling and the Clausius-Clapeyron equation, capillary rise and bubbles, Stokes' law and Poiseuille's law. With a worked example, practice, a program and questions to check yourself.
Introduction to Three-Dimensional GeometryHigh School (11–12)
Loci, Spheres and Cuboid Problems: Quick Revision
A brief note on loci, spheres and cuboid problems: the sphere, the plane of equal distances, loci from a sum or a ratio of distances, the point equally far from four points, and cubes and cuboids with coordinates. With practice, a program and questions to check yourself.
Biodiversity and ConservationHigh School (11–12)
Conserving Biodiversity: Quick Revision
A brief note on Conserving Biodiversity: in situ and ex situ methods, hotspots, protected areas, sacred groves, the Red Data Book and its categories, and the international efforts, with the usual slips and questions to check yourself.
Biology by ComputerHigh School (11–12)
Growth and Populations by Computer: Quick Revision
A brief note on Growth and Populations by Computer: exponential growth, log axes, doubling time, logistic growth stepped in code, and fitting curves with polyfit and curve_fit. With a worked example, practice, a program and questions to check yourself.
Correlation and RegressionHigh School (9–10)
Correlation and Cause: Quick Revision
A brief note on correlation and cause: lurking variables, the reasons two variables move together, Simpson's paradox, straightening a curve with a logarithm or a square root, and questions for claims in the news. With a worked example, practice, a program and questions.
Electromagnetic WavesHigh School (11–12)
The Electromagnetic Spectrum: Quick Revision
A brief note on The Electromagnetic Spectrum. It covers the bands, their sources and uses, Wien's law and the atmosphere, with a worked example and questions to check yourself.