ESE 2021 Technical Quiz 9 || Circuits Analysis and Applications of Diodes, BJT and MOSFET-1

In a forward biased region of a pn junction diode:

A p-n junction diode has a reverse saturation current rating of 50 nA at 32°C. Assuming at 32°C is 26 mV. The dynamic AC resistance of the diode at 32°C is _____ mΩ (forward voltage drop of diode is 0.5 V)

Assuming diode are ideal in figure the current in diode D₁ is

Determine the region of operation of silicon transistor shown in circuit below:

[Assume: β = 150, V_{BE (sat)} = 0.8 V, V_{BE (active)} = 0.7 V, V_{CE (sat)} = 0 V, V_D for diodes D₁ & D₂ is 0.7 V]

For the given transistor comment in which region the transistor is operating?