Physics

The physics library

Written explainers for all 68 core topics, organised by the physics rather than by any exam board.

Every topic

MEASUREMENTS

• SI units and prefixes
• Uncertainty and error
• Estimation and orders of magnitude

MECHANICS

• Scalars and vectors
• Moments and equilibrium
• Motion graphs and the SUVAT equations
• Projectile motion
• Newton's laws and the resultant force
• Mass and weight
• Drag and terminal speed
• Momentum and impulse
• Work, energy and power
• Conservation of energy

MATERIALS

• Density and Hooke's law
• Stress, strain and the Young modulus

WAVES

• Progressive waves
• Longitudinal, transverse and polarisation
• Stationary waves
• Refraction and total internal reflection
• Diffraction and the single slit
• Interference and Young's double slit
• Diffraction gratings

QUANTUM PHENOMENA

• The photoelectric effect
• Collisions of electrons with atoms
• Energy levels and photon emission
• Wave-particle duality

PARTICLES

• Constituents of the atom
• Stable and unstable nuclei
• Antimatter and photons
• Particle interactions and exchange particles
• Classification of particles
• Quarks and antiquarks
• Conservation laws

ELECTRICITY

• Current, charge and the direction problem
• Current-voltage characteristics
• Resistivity and superconductivity
• Circuits and Kirchhoff's laws
• Potential dividers
• EMF and internal resistance

PERIODIC MOTION

• Circular motion
• Simple harmonic motion
• SHM systems: pendulums and springs
• Forced vibrations and resonance

THERMAL PHYSICS

• Thermal energy transfer and specific heat capacity
• Ideal gases and the gas laws
• Molecular kinetic theory

GRAVITATIONAL FIELDS

• The field concept
• Newton's law of gravitation
• Gravitational potential
• Orbits and satellites

ELECTRIC FIELDS

• Coulomb's law and electric field strength
• Electric potential
• Comparing electric and gravitational fields

CAPACITANCE

• Capacitors and energy stored
• Charging and discharging
• The time constant and exponential decay

MAGNETIC FIELDS

• Magnetic flux density and the force on a wire
• Force on a moving charge
• Magnetic flux and flux linkage
• Electromagnetic induction: Faraday and Lenz
• Alternating currents
• Transformers

NUCLEAR PHYSICS

• Rutherford scattering and the nuclear atom
• Radioactive decay and half-life
• Nuclear radius and density
• Mass-energy and binding energy
• Fission and fusion
• Nuclear reactors and safety