Photo-electrons: When photons strike certain materials, they can knock out electrons from the material's surface. These ejected electrons are called photo-electrons.
Einstein relationship: The Einstein relationship states that the energy (E) of a photon is equal to Planck's constant (h) multiplied by its frequency (f), expressed as E = hf.
Wave-particle duality:This term refers to the concept that particles like photons can exhibit both wave-like and particle-like behavior depending on how they are observed or interacted with.