Describe the photoelectric effect and explain why it made modifications to the rutherford model necessary.

The emission of free carriers or electrons taking place when light falls into a substance is termed as the photoelectric effect. On the basis of the Rutherford model, the light of any energy should possess the tendency to cause the electrons to leave the atom and get emitted.  

The energy obtained from the emitted electrons should be associated with the intensity of the light. However, the energy of the electron is in the real sense only associated with the energy of the light.