Modern & Engineering Physics Advanced

A wave transfers energy without transferring matter. v = fλ links speed, frequency and wavelength. Light exhibits reflection, refraction (Snell's law) and interference — principles behind lenses, fibre optics and cameras.

Einstein showed the speed of light is constant for all observers. Consequences include time dilation, length contraction and mass-energy equivalence E = mc². GPS satellites must correct for relativistic effects to stay accurate.

At small scales energy is quantised. Light behaves as both wave and particle (photons); electrons have wavelike properties. The uncertainty principle limits simultaneous knowledge of position and momentum. Quantum mechanics explains the periodic table and chemical bonding.

Quantum physics enables semiconductors: doping silicon creates p- and n-type material whose junction forms a diode or transistor — the building block of all modern electronics. Lasers, LEDs, solar cells and MRI all rest on modern physics.