$A$ $N-P-N$ transistor is connected in common emitter configuration (see figure) in which the collector voltage drop across the load resistance $(800 \; \Omega)$ connected to the collector circuit is $0.8 \; V$. The collector current is .............. $mA$.

In common emitter mode of a transistor, the current gain is $8$. The input impedance is $25 \, k\Omega$ and load resistance is $75 \, k\Omega$. The power gain is

For a transistor in the active region:
$(a)$ Base,emitter,and collector regions should have similar size and doping concentrations.
$(b)$ The base region must be very thin and lightly doped.
$(c)$ The emitter-base junction is forward-biased and the base-collector junction is reverse-biased.
$(d)$ Both the emitter-base junction and the base-collector junction are forward-biased.
Which one of the following pairs of statements is correct?

In a $CE$ transistor,when the base current increases by $60 \mu A$,the change in base-emitter voltage is $1.2 \ V$. Then the input resistance is: (in $\Omega$)

An $N-P-N$ transistor in a common emitter mode is used as a simple voltage amplifier with a collector current of $4 \ mA$. The terminal of an $8 \ V$ battery is connected to the collector through a load resistance $R_L$ and to the base through a resistance $R_B$. The collector-emitter voltage $V_{CE} = 4 \ V$,base-emitter voltage $V_{BE} = 0.6 \ V$ and base current amplification factor $\beta_{d.c.} = 100$. Calculate the values of $R_L$ and $R_B$.

In a common emitter amplifier,a.c. current gain is $40$ and input resistance is $2 \ k\Omega$. The load resistance is given as $10 \ k\Omega$. Then the voltage gain is