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

$A$ photodiode is a device

The current in the forward bias is known to be more $(\sim mA)$ than the current in the reverse bias $(\sim \mu A)$. What is the reason then to operate the photodiodes in reverse bias?

Statement $-I$: $A$ photodiode operates in reverse bias.
Statement $-II$: The fractional change due to the photo-effects on the minority carrier dominated reverse bias current is more easily measurable than the fractional change in the forward bias current.

The photocurrent in a photodiode depends on

Describe the construction, working, and use of a solar cell.