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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Alternating CurrentHigh School (11–12)
Transformers and LC Oscillations: Quick Revision
A brief note on Transformers and LC Oscillations. The turns ratio and losses of a transformer. Why power is sent at a high voltage. The frequency and energy of an LC circuit. A worked example and questions to check yourself.
Bonding: Valence Bond and Crystal Field TheoryHigh School (11–12)
Bonding in Coordination Compounds: Quick Revision
A brief note on Bonding in Coordination Compounds: hybridisation, spin-only moments, crystal field splitting, CFSE, colour and stability. 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.
Circulatory SystemHigh School (11–12)
The Cardiac Cycle, the ECG, Regulation and Disorders: Quick Revision
A brief note on The Cardiac Cycle, the ECG, Regulation and Disorders: the stages of the cycle, the heart sounds and the cardiac output. It also covers the ECG, the control of the heart and the disorders, 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.
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.
Alternating CurrentHigh School (11–12)
Series LCR Circuits and Resonance: Quick Revision
A brief note on Series LCR Circuits and Resonance: impedance and phase of a series circuit, resonance, the quality factor and the bandwidth, and average power with the power factor, with a worked example and questions to check yourself.
Isomerism in Coordination CompoundsHigh School (11–12)
Isomerism in Coordination Compounds: Quick Revision
A brief note on Isomerism in Coordination Compounds: structural isomers, cis and trans, fac and mer, optical isomers and how to count them. 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.
Circulatory SystemHigh School (11–12)
The Heart and the Circulatory Pathways: Quick Revision
A brief note on The Heart and the Circulatory Pathways: open and closed circulation, the hearts of vertebrates, the human heart with its nodal tissue, and the two loops of the double circulation. It has 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.
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.
Alternating CurrentHigh School (11–12)
AC Voltage and Simple AC Circuits: Quick Revision
A brief note on AC Voltage and Simple AC Circuits: peak and rms values, a resistor, a coil and a capacitor on an AC source, reactance, phasors and phase, with a worked example, practice and questions to check yourself.
Werner's Theory, Ligands and NomenclatureHigh School (11–12)
Werner's Theory and Naming Complexes: Quick Revision
A brief note on Werner's theory and naming complexes: the two valences, ligands and the coordination number, the oxidation state of the metal and the IUPAC rules for names and formulae. With a worked example, practice, a program and questions to check yourself.
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.
Circulatory SystemHigh School (11–12)
Blood, Blood Groups, Coagulation and Lymph: Quick Revision
A brief note on Blood, Blood Groups, Coagulation and Lymph: the plasma and the blood cells with their counts, the ABO and Rh groups, the steps of clotting and the lymph, 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.
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.
Electromagnetic InductionHigh School (11–12)
Generators and Induction Problems: Quick Revision
A brief note on Generators and Induction Problems: the emf of a turning coil, rods and frames in fields, and the LR circuit, with a worked example, practice and questions to check yourself.
Lanthanoids and Actinoids (f-Block)High School (11–12)
The Lanthanoids and Actinoids: Quick Revision
A brief note on The Lanthanoids and Actinoids: the 4f and 5f rows, their oxidation states, the lanthanoid contraction and its effects, and uses. 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.
Respiratory SystemHigh School (11–12)
Carbon Dioxide Transport, Control of Breathing and Respiratory Disorders: Quick Revision
A brief note on Carbon Dioxide Transport, Control of Breathing and Respiratory Disorders. It covers the three forms of carbon dioxide, the centres of the brain, and asthma, emphysema and the dust diseases, with the usual slips and questions.
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.
Electromagnetic InductionHigh School (11–12)
Eddy Currents and Inductance: Quick Revision
A brief note on Eddy Currents and Inductance: why eddy currents brake and heat a conductor, self-inductance and its emf, mutual inductance, and the energy stored in a coil, with a worked example, practice and questions to check yourself.