Two identical P-N junctions may be connected in series with a battery in three ways. The potential drops across the two P-N junctions are equal in

 

The circuit has two oppositely connected ideal diodes in parallel. What is the current flowing in the circuit?

In the following, which one of the diodes is reverse biased?

The electrical conductivity of a semiconductor increases when electromagnetic radiation of wavelength shorter than $2480 \mathrm{nm}$ is incident on it. The band gap, in ($\mathrm{eV}$), for the semiconductor is,

A full wave rectifier circuit along with the output is shown in the figure. The contribution from diode ‘1’ is