IGCSE Physics Formula Sheet

Distance divided by time. For average speed, use total distance over total time. The unit is m/s or km/h.

Change in velocity divided by time taken. Deceleration is simply negative acceleration.

Newton's second law. The net force on an object equals its mass times its acceleration. Mass in kg, acceleration in m/s².

Weight is the force of gravity on an object. On Earth, g ≈ 9.8 m/s² (often rounded to 10 in IGCSE).

Mass times velocity. Momentum is conserved in all collisions, this is key for collision calculations.

Force multiplied by distance moved in the direction of the force. Measured in joules (J).

Energy of a moving object. Note that velocity is squared, doubling speed quadruples the kinetic energy.

Energy stored due to height above a reference point. Often used with energy conservation problems.

No machine is 100% efficient, energy is always lost to heat, sound, or friction.

Speed equals frequency times wavelength. Works for all waves, sound, light, water.

Relates angles of incidence and refraction when light passes between media with different refractive indices.

Voltage equals current times resistance. The most-used formula in IGCSE Physics, learn to rearrange it fluently.

Power in watts equals current times voltage. Can also be written as P = I²R or P = V²/R.

Energy in joules equals power in watts times time in seconds. For kWh, use power in kW and time in hours.