Cambridge IGCSE·Co-ordinated Sciences 0654·Physics
Waves
Key knowledge — Waves
Formulas & equations
Wave speed = frequency × wavelength (v = fλ)Period = 1 ÷ frequency (T = 1/f)Snell's law: n₁ sin θ₁ = n₂ sin θ₂Refractive index: n = sin i ÷ sin r = speed in vacuum ÷ speed in mediumCritical angle: sin C = 1/n
Key facts & rules
- Transverse wave: oscillations perpendicular to direction of travel (light, water, EM waves).
- Longitudinal wave: oscillations parallel to direction of travel (sound, P-waves).
- Amplitude: maximum displacement from equilibrium — related to energy/loudness.
- Frequency (Hz): number of complete waves per second.
- Wavelength: distance between two adjacent identical points.
- Reflection: angle of incidence = angle of reflection (measured from normal).
- Refraction: wave changes speed when entering a new medium → changes direction.
- Total internal reflection: occurs when angle of incidence > critical angle (light going dense → less dense).
- Electromagnetic spectrum (low to high frequency): radio → microwave → infrared → visible → UV → X-ray → gamma.
- All EM waves travel at 3 × 10⁸ m/s in a vacuum.
IGCSE Physics — Waves
3869 Cambridge IGCSE 0654 physics past paper questions on waves, organised by subtopic. Pick a subtopic to start practising.
About waves on IGCSE 0654
Wave properties, the electromagnetic spectrum, reflection and refraction, sound and light. The largest Physics topic in this dataset.