hello in this chapter every scientist say that electron escape if radiation fall into any metal surface but did you tell me why electron wrere not escape in the case of solar cells means in solar cells electron absord energy ans they create electricity but in photoelectric effects its say its has some work function to esape throught surface overall tell me the most uniqe difference in solar cell and photoelectric effects and one common thing in both

CBSE Class 12-science Answered

hello

in this chapter every scientist say that electron escape if radiation fall into any metal surface

but did you tell me why electron wrere not escape in the case of solar cells

means in solar cells electron absord energy ans they create electricity

but in photoelectric effects its say its has some work function to esape throught surface

overall tell me the most uniqe difference in solar cell and photoelectric effects

and one common thing in both

Asked by saggugurupal | 04 Nov, 2016, 02:43: PM

Expert Answer

In case of photoelectric effect and solar cells incident radiation causes electrons to escape and help conduct electricity.

But, the primary difference is that in photoelectric effect from a metal surface, visible light is unable to eject electrons whereas for solar cells visible light is used to eject electrons.

This comes because solar cells use semiconductors. Now, semiconductors have a small energy band gap similar to work function. But, this gap is small enough such that visible light is able to cause ejection of electrons. In metals electrons are held tightly and so ejection requires high energy. This energy is the work function. So, visible light is unable to eject electrons and only radiation of higher frequency are able to do so.

Hence, to summarise we can say that the unique difference is photoelectric effect cannot be brought about by visible light while electricity can be generated from solar cell using visible light. The common thing between the two is that electrons are ejected from the surface due to incident radiation.

Answered by Romal Bhansali | 04 Nov, 2016, 03:17: PM