The Particle Nature of EM Radiation The Particle Nature of Light In classical wave theory, electromagnetic (EM) radiation is assumed to behave as a wave This is demonstrated by the fact EM radiatio...
The Electronvolt The electronvolt is a unit which is commonly used to express very small energies This is because quantum energies tend to be much smaller than 1 Joule The electronvolt is derived f...
The Photoelectric Equation Since energy is always conserved, the energy of an incident photon is equal to: The work function + the maximum kinetic energy of the photoelectron The energy within a ph...
The Photoelectric Effect The photoelectric effect is the phenomena in which electrons are emitted from the surface of a metal upon the absorption of electromagnetic radiation Electrons removed from...
Energy of a Photon Photons are fundamental particles which make up all forms of electromagnetic radiation A photon is a massless “packet” or a “quantum” of electromagnetic energy What this means is...
Wave-Particle Duality Light can behave as a particle (i.e. photons) and a wave This phenomenon is called the wave-particle nature of light or wave-particle duality Light interacts with matter, such...
Pulse-Echo Technique Foetal Scanning In medicine, ultrasound can be used to construct images of a foetus in the womb An ultrasound detector is made up of a transducer that produces and detects a be...
Transmission & Reflection of Waves When waves are incident on the interface between two different media, they are either transmitted or reflected 'Incident on' simply means 'to meet' The interf...
The de Broglie Equation Using ideas based upon the quantum theory and Einstein’s theory of relativity, de Broglie theorised that not only do EM waves sometimes behave as particles, but that very sm...
