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• PHYS PRACTICE
• Einstein suggested that EM waves and their carried energy existed as discrete packets: PHOTONS.
• Einstein saw these photons of light as having ONE-on-ONE PARTICLE LIKE interactions with an electron in a metal surface.
• A photon would transfer all its energy to A SINGLE SPECIFIC ELECTRON
• Acc to the Photon model:
• WHEN LIGHT HITS ITS SURFACE, THE METAL IS BOMBARDED WITH PHOTONS.
• WHEN A PHOTON COLLIDES WITH A FREE ELECTRON, THE ELECTRON WILL GAIN ENERGY EQUAL TO HF.
• BEFORE AN ELECTRON LEAVES THE SURFACE OF THE METAL, IT NEEDS TO HAVE ENOUGH ENERGY TO BREAK THE BONDS HOLDING IT THERE. THIS ENERGY IS CALLED THE WORK FUNCTION (PHI SYMBOL), AND ITS VALUE DEPENDS ON EACH METAL.
• photoelectric effect
• THE PHOTON MODEL EXPLAINS THE THRESHOLD FREQUENCY.
• If the energy gained by an electron (on surface of metal) is GREATER than the WORK FUNCTION, the electron is emitted.