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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Current ElectricityHigh School (11–12)
Cells, the Meter Bridge and the Potentiometer: Quick Revision
A brief note on Cells, the Meter Bridge and the Potentiometer: cells in series, in parallel and in rows, the balance rules of the meter bridge and the potentiometer, and the usual slips, with practice and a program.
Purification and Analysis of Organic CompoundsHigh School (11–12)
Purification and Analysis of Organic Compounds: Quick Revision
A brief note on Purification and Analysis of Organic Compounds: sublimation, crystallisation, distillation, chromatography and Rf, the tests for each element, and the Liebig, Dumas, Kjeldahl and Carius calculations. With a worked example, practice, a program and questions to check yourself.
CirclesHigh School (9–10)
Tangents to a Circle: Quick Revision
A brief note on Tangents to a Circle: the tangent and the radius, the two equal tangents from an outside point, and the circle inside a triangle or a four-sided figure. With a worked example, practice, a program and questions to check yourself.
Anatomy of Flowering PlantsHigh School (11–12)
Secondary Growth: Quick Revision
A brief note on Secondary Growth: how the vascular cambium and the cork cambium make a dicot stem thicker, annual rings, heartwood and sapwood, and the bark and lenticels, with a worked example and questions.
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.
Averages: Mean, Median and ModeMiddle Stage (6–8)
A Data Project from Question to Report
The Weather Project: the six steps of a data project, showing a month of weather, its centre, spread and chances, linked days, and an honest report with a limit. With a worked example, practice, a program and questions.
Current ElectricityHigh School (11–12)
Current, Drift Velocity and Resistivity: Quick Revision
A brief note on Current, Drift Velocity and Resistivity: the drift of electrons, current density and mobility, resistivity and R = ρL/A, the effect of temperature, and the colour code, with a worked example, practice and questions to check yourself.
Electronic Effects and Reaction IntermediatesHigh School (11–12)
Electronic Effects and Reaction Intermediates: Quick Revision
A brief note on Electronic Effects and Reaction Intermediates: homolytic and heterolytic fission, free radicals, carbocations and carbanions, the inductive effect, resonance, hyperconjugation, and the types of reaction. With a worked example, practice, a program and questions to check yourself.
CirclesHigh School (9–10)
Cyclic Quadrilaterals: Quick Revision
A brief note on Cyclic Quadrilaterals: the opposite-angle theorem, the exterior angle, the converse, cyclic trapezia and other shapes, and ways to show that four points lie on a circle. With a worked example, practice, a program and questions to check yourself.
Anatomy of Flowering PlantsHigh School (11–12)
Tissue Systems and the Anatomy of Root, Stem and Leaf: Quick Revision
A brief note on Tissue Systems and the Anatomy of Root, Stem and Leaf: the three tissue systems, and how to read a dicot and a monocot root, stem and leaf in section. With a worked example, practice, a program 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.
Probability and ChanceMiddle Stage (6–8)
Probability: Quick Revision
A brief note on Chance: probability by counting, the chance that something does not happen, relative frequency and the long run, two events together, at least one, and taking without putting back. With a worked example, practice, a program and questions.
Atoms and Atomic SpectraHigh School (11–12)
The Atom: Rutherford, Bohr and Spectra: Quick Revision
A brief note on The Atom: Rutherford, Bohr and Spectra: the scattering of alpha particles, the closest approach, Bohr's model with its radius, speed and energy, and the series of hydrogen, with practice and a program.
Classification, IUPAC Nomenclature and IsomerismHigh School (11–12)
Classification, Nomenclature and Isomerism: Quick Revision
A brief note on Classification, Nomenclature and Isomerism: the shapes of carbon compounds, the four ways to write a structure, functional groups, the IUPAC naming rules, and the kinds of isomerism. With a worked example, practice and a program.
CirclesHigh School (9–10)
Chords, Arcs and the Angles They Make: Quick Revision
A brief note on Chords, Arcs and the Angles They Make: the parts of a circle, equal chords, the perpendicular from the centre, and the angle that an arc makes at the centre and at the rim. With a worked example, practice, a program and questions.
Anatomy of Flowering PlantsHigh School (11–12)
Meristematic and Permanent Tissues of Plants: Quick Revision
A brief note on Meristematic and Permanent Tissues of Plants: the meristems and what each adds, the three simple tissues, xylem and phloem and their cells, with the usual slips, a worked example, practice, a program 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.
Spread of DataMiddle Stage (6–8)
Range, IQR and Standard Deviation: Quick Revision
A brief note on Spread: the range, quartiles and the IQR, box plots, the variance and the standard deviation, which measure to use, and what adding or multiplying does to the spread. With a worked example, practice, a program and questions.
Dual Nature of Radiation and MatterHigh School (11–12)
Dual Nature of Radiation and Matter: Quick Revision
A brief note on Dual Nature of Radiation and Matter. It covers the photoelectric laws, Einstein's equation, photons, de Broglie waves and the Davisson and Germer experiment, with a worked example and questions to check yourself.
Oxidation Number and Types of Redox ReactionsHigh School (11–12)
Redox and Electrode Potentials: Quick Revision
A brief note on Redox and Electrode Potentials: the Daniell cell, E° and the cell potential, the electrochemical series and ΔG° = −nFE°. With a worked example, practice, a program and questions to check yourself.
Heights and DistancesHigh School (9–10)
Heights and Distances with Two Triangles: Quick Revision
A brief note on Heights and Distances with Two Triangles: two observation points, a tower on a building, moving objects and the width of a river. With a worked example, practice, a program and questions to check yourself.
Human Health and DiseaseHigh School (9–10)
Infectious Diseases and Immunity: Quick Revision
A brief note on Infectious Diseases and Immunity: infectious agents, how they spread, treatment, prevention, vaccines and HIV. With a worked example, practice, a program 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.
Data and SamplingMiddle Stage (6–8)
Data Tables, Kinds of Data and Fair Samples
A brief note on What Is Data?: tables of cases and variables, the four kinds of data, and how to choose a fair sample and ask a fair question. With a worked example, practice, a program and questions.
Doppler EffectHigh School (11–12)
Beats, Resonance and the Doppler Effect: Quick Revision
A brief note on Beats, Resonance and the Doppler Effect: the beat frequency, the resonance tube and its end correction, and the Doppler rule for sound, with practice and a program.