Question

In the following diagram, which bulb out of `B_(1)` and` B_(2)` will glow and why?

Draw a diagram of an illuminated p-n junction solar cell
Explain briefly the three processes due to which generation of emf takes place in a solar cell.

Answer 1

(a) As `D_(1)` is in forward bias and `D_(2)` is in reverse bias so, bulb B_(1) will glow
(b) (i) Generation of e-h pair due to light with hv ` lt (E_(delta))` . Close to the junction
(ii)Separation of electrons and holes due to electric field of depletion layer.
(iii) Collection of electron by n -side (front and back ) contact .Thus,
p-side becomes positive and n-side negative giving rise to photovoltage.