In a common emitter configuration with suitable bias, it is given that $${R_L}$$ is the load resistance and $${R_{BE}}$$ is small signal dynamic resistance (input side). Then, voltage gain, current gain and power gain are given, respectively, by :

$$\beta $$ is curret gain, $${{\rm I}_B},{{\rm I}_C}$$ and $${{\rm I}_E}$$ are respectively base, collector and emitter currents.

The current gain of a common emitter amplifier is 69. If the emitter current is 7.0 mA, collector current is :

What is the conductivity of a semiconductor sale having electron concentration of $$5 \times {10^{18}}\,\,{m^{ - 3}},$$ hole concentration of $$5 \times {10^{19}}\,\,{m^{ - 3}},$$ electron mobility of 2.0 m² V^$$-$$1 s^-1 and hole mobility of 0.01 m² V^$$-$$1 s^$$-$$1 ?

(Take charge of electronas 1.6 $$ \times $$ 10 ^$$-$$19 c)

The V-I characteristic of a diode is shown in the figure. The ratio of forward to reverse bias resistance is :