Photoelectric Effect - Answering Questions

Seite 1

Photoelectric Effect - Answering Questions

Threshold frequency - minimum frequency required for electrons to have enough energy to be emitted from a metal surface.

Work function - minimum energy required for electrons to be emitted from a metal surface.

Why emitted electrons have a range of kinetic energies up to a maximum - photon energy dependant on frequency, 1-1 interaction between photon and electron, electrons maybe deep in the metal and require more energy, state equation, electron must overcome work function, energy of photon is fixed.

When decreasing frequency but keeping intensity constant - decrease in maximum energy of the electrons due to lower photon energy

Effect of doubling intensity but keeping frequency constant - increase in photons cause increase in emitted electrons, number of emitted electrons doubled

With reference to work function, why electrons won't be emitted if frequency is below a certain value - work function is minimum energy needed to release electron, electron won't have enough energy if frequency is below the certain value

Why threshold frequency supports particle-like nature of electromagnetic waves (6 marker) - define threshold frequency, light travels as photons, 1-1 interaction between photons and electrons, photon energy dependent on frequency, emission occurs instantaneously, no emission unless frequency is more than or equal to threshold frequency as photon energy would be less than work function otherwise.