Electromagnetic waves and interference

What this note covers

1. Electromagnetic waves carry energy without a material medium
2. Phase and superposition determine reinforcement and cancellation
3. Double-slit geometry connects path difference to fringe spacing
4. Diffraction and interference reveal wave behaviour at apertures
5. Intensity, amplitude and photon rate describe different quantities
6. Measure wavelength from a pattern with defensible uncertainty

6 sections · 10 key terms & formulas · 6 common mistakes