Chapter 1: Electric Charges and Fields
This chapter introduces electric charge, the source of all electrical effects. It explains the two kinds of charge and the key facts that charge is quantised, coming only in whole units, and conserved. It develops Coulomb's law for the inverse square force between charges, the electric field and the field lines that picture it, and the electric dipole. The chapter then builds to Gauss's law, which links the flux through a closed surface to the charge inside, and uses it to find the field of a charged sphere, sheet and wire. With clear diagrams of Coulomb's law, field lines and a Gaussian surface, it lays the foundation for the whole of electrostatics.
Chapter 2: Electrostatic Potential and Capacitance
This chapter develops the energy side of electrostatics. It explains electric potential as the energy per unit charge, the potential of a point charge, and equipotential surfaces that field lines always cross at right angles. It then introduces the capacitor, a device that stores charge and energy, defining capacitance as charge per volt and examining the parallel plate capacitor. The chapter covers combinations of capacitors in series and parallel and the energy stored in a charged capacitor. With clear diagrams of equipotentials, a parallel plate capacitor and series and parallel combinations, it shows how charge and energy are stored and controlled in circuits.
Chapter 3: Current Electricity
This chapter develops the flow of charge in circuits. It explains electric current as the rate of flow of charge, Ohm's law linking voltage, current and resistance, and the idea of resistance and resistivity. It covers how resistors combine in series and parallel, and how cells drive current, introducing electromotive force and the internal resistance that lowers the terminal voltage. The chapter ends with the Wheatstone bridge, a precise way to measure resistance. With clear diagrams of a simple circuit, an ohmic voltage to current graph and the Wheatstone bridge, it builds a solid understanding of how circuits behave and are analysed.
Chapter 4: Moving Charges and Magnetism
This chapter develops the deep link between electricity and magnetism. It explains how a current produces a magnetic field, with circular field lines around a wire, and how a magnetic field exerts a force on a moving charge and on a current carrying wire. It develops the solenoid, which behaves like a bar magnet and forms the electromagnet, and the moving coil galvanometer that measures current. With clear diagrams of the field around a wire, the force on a moving charge and a solenoid, it shows how moving charges create magnetism and how magnetism drives motors and instruments.
Chapter 5: Magnetism and Matter
This chapter develops magnets and how materials respond to magnetic fields. It explains the bar magnet and its field lines running from north to south, the fact that magnetic poles always come in pairs, and the Earth behaving as a giant magnet that a compass lines up with. It develops the three classes of magnetic material, diamagnetic, paramagnetic and ferromagnetic, and the hysteresis loop that shows magnetisation lagging the applied field, leading to permanent magnets and electromagnets. With clear diagrams of a bar magnet, the material classes and a hysteresis loop, it explains the magnetic behaviour of matter.
Chapter 6: Electromagnetic Induction
This chapter develops how a changing magnetic field produces electricity. It explains magnetic flux, Faraday's law that the induced electromotive force equals the rate of change of flux, and Lenz's law that the induced current always opposes the change, an expression of conservation of energy. It develops the alternating current generator, in which a spinning coil produces alternating current, and self and mutual induction with the transformer. With clear diagrams of induction, Lenz's law and the generator, it shows the principle behind almost all electricity generation in the world today.
Chapter 7: Alternating Current
This chapter develops alternating current, the form in which mains electricity is supplied. It explains why AC reverses regularly, the root mean square value that gives its effective heating value, and how resistors, inductors and capacitors respond to AC at different frequencies. It develops the series LCR circuit and its impedance, the special case of resonance where the current is greatest and which is used to tune circuits, and the transformer that reduces transmission losses. With clear diagrams of an AC waveform, an LCR circuit and a phasor diagram, it explains the behaviour of AC circuits.
Chapter 8: Electromagnetic Waves
This chapter develops the nature of light as an electromagnetic wave. It explains how oscillating electric and magnetic fields, at right angles to each other and to the direction of travel, form a transverse wave that needs no medium and travels at the speed of light. It develops the wave equation linking speed, frequency and wavelength, and the full electromagnetic spectrum from radio waves to gamma rays, with visible light as a thin slice in the middle. With clear diagrams of an electromagnetic wave, a labelled wave and the spectrum, it shows how a single family of waves carries everything from radio to gamma rays.
Chapter 9: Ray Optics and Optical Instruments
This chapter develops light as travelling rays that reflect and refract. It explains the law of reflection and mirrors, refraction and Snell's law with the refractive index, and how a ray bends toward the normal entering a denser medium. It develops image formation by lenses, tracing rays through a convex lens to a real inverted image, and the dispersion of white light into a spectrum by a prism. It closes with optical instruments such as the eye, microscope and telescope. With clear diagrams of refraction, a lens and a prism, it explains how mirrors and lenses form images.
Chapter 10: Wave Optics
This chapter develops the wave nature of light through effects that rays cannot explain. It explains interference, where overlapping waves brighten when in step and cancel when out of step, and Young's double slit experiment, whose pattern of bright and dark fringes proved that light is a wave. It develops how the path difference sets each fringe, and diffraction, where light bends through a narrow slit to give a wide central band with weaker side bands. With clear diagrams of interference, the double slit and single slit diffraction, it shows how these effects prove light is a wave and let us measure its wavelength.
Chapter 11: Dual Nature of Radiation and Matter
This chapter develops the surprising idea that light and matter each have both a wave and a particle nature. It explains the photoelectric effect, in which light ejects electrons only above a threshold frequency, and Einstein's explanation using photons, packets of light energy given by the frequency. It develops the photon and de Broglie's matter waves, in which a moving particle has a wavelength, confirmed by electron diffraction, leading to wave particle duality. With clear diagrams of the photoelectric effect, a kinetic energy graph and matter waves, it introduces a foundation of modern quantum physics.
Chapter 12: Atoms
This chapter develops the structure of the atom. It explains Rutherford's alpha scattering experiment, which revealed a tiny, dense, positive nucleus with electrons around it and mostly empty space. It develops Bohr's model, in which electrons occupy fixed energy levels and do not radiate within them, keeping the atom stable, and how a jump to a lower level emits a photon of fixed energy. This explains the line spectra unique to each element and shows that atomic energy is quantised. With clear diagrams of Rutherford scattering, the Bohr model and energy levels, it explains how atoms are built and why they emit light.
Chapter 13: Nuclei
This chapter develops the nucleus and its immense store of energy. It explains the composition of the nucleus from protons and neutrons, isotopes, and the mass energy relation by which a small mass holds great energy. It develops binding energy from the missing mass, the binding energy per nucleon curve that peaks near iron and sets nuclear stability, radioactivity by alpha, beta and gamma decay described by the half-life, and the release of energy in nuclear fission and fusion. With clear diagrams of the nucleus, the binding energy curve and the decay types, it explains the source of nuclear energy.
Chapter 14: Semiconductor Electronics
This chapter develops the semiconductors at the heart of modern electronics. It explains energy bands and how the size of the band gap makes a conductor, semiconductor or insulator, and how doping creates n-type material with free electrons and p-type material with holes. It develops the p-n junction and its depletion region, the diode that conducts in one direction and is used to rectify alternating current, and the basic logic gates that build digital circuits. With clear diagrams of energy bands, a p-n junction and a diode characteristic, it explains the components behind every electronic device.
