In the Photoelectric Effect, what is mean by 'threshold frequency' and how does the magnitude a photons frequency effect the electron it is absorbed by?

The threshold frequency is the minimum frequency a photon can be and still just overcome the work function (Φ) of a particular material. The threshold frequency is directly proportional to the work function and is given by f=E/h, where E is equal to Φ, f is the threshold frequency and h is Planck's constant.Providing the frequency of the photon is greater than the threshold frequency, the electron absorbing the photon will escape the material. However, if the frequency of the photon is greater than this the electron will have excess energy after escaping the surface of the material, which is present as kinetic energy, given by Ek = E - Φ (E is given by E=hf).

JH

Related Physics A Level answers

All answers ▸

Initially, trucks A and B are travelling in opposite directions. A has mass 1000 kg and is travelling at speed 7ms^-1. B has mass 4000kg and is travelling at speed 2ms^-1. What is their speed and direction after collision if they move together?


Why does a body engaged in uniform circular motion do no work?


State the principle of superposition of waves and illustrate it schematically.


An electron is accelerated through a uniform electric field of strength, E= 20 [N/C]. Determine the speed after the the electron travels 0.5 m from rest.