A-Level Physics Formula Sheet

For constant acceleration only. Always define a positive direction and stick to it.

Stress over strain. Measured from the gradient of the linear region of a stress-strain graph.

Conserved in all collisions. In 2D, conserve momentum separately in x and y directions.

For ohmic conductors at constant temperature. Combine with Kirchhoff's laws for circuit analysis.

Resistance depends on material (ρ), length (l), and cross-sectional area (A).

Three forms — use whichever matches your known quantities.

Terminal PD = EMF − lost volts. Plot V against I to find EMF (intercept) and r (gradient).

Speed = frequency × wavelength. The speed of electromagnetic waves in vacuum is 3 × 10⁸ m/s.

Energy of a photon. h = 6.63 × 10⁻³⁴ J·s. Higher frequency = higher energy.

Every moving particle has a wave nature. Smaller mass and slower speed = longer wavelength.

Photon energy = work function + maximum kinetic energy of emitted electron. Below threshold frequency, no emission.

Exponential decay. λ is the decay constant, related to half-life by λ = ln 2 / t½.

Time for half the nuclei to decay. Independent of the amount of substance.

Mass and energy are interchangeable. Used to calculate energy released in nuclear reactions from mass defect.