In an $LED$,when forward bias is increased (starting from zero),the intensity of emitted light will:

Why are $Si$ and $GaAs$ preferred materials for solar cells?

$A$ $p-n$ junction photodiode is fabricated from a semiconductor with a band gap of $2.5 eV$. It can detect a signal of wavelength: (Given: Planck's constant $h = 6.6 \times 10^{-34} Js$,speed of light $c = 3 \times 10^8 m/s$,elementary charge $e = 1.6 \times 10^{-19} C$)

Consider a situation in which reverse biased current of a particular $P-N$ junction increases when it is exposed to light of wavelength $\lambda \le 621 \, nm$. During this process,enhancement in carrier concentration takes place due to the generation of hole-electron pairs. The value of the band gap is nearly (in $eV$):

The energy gap of an $LED$ is $2.4 eV$. When the $LED$ is switched $ON$,the momentum of the emitted photons is

In the working of a photodiode,the reverse current depends on