When $NPN$ transistor is used as an amplifier,

The thinnest part of a transistor is . . . . . .

In a common emitter transistor amplifier circuit,the current gain $\alpha = 0.8$. If the base current changes by $3 \mu A$,then the collector current changes by: (in $\mu A$)

Input signal to a common emitter amplifier having a voltage gain of $1000$ is given by $v_i = (0.004 \, V) \sin(\omega t + \pi/2)$. The corresponding output signal is

For a given transistor amplifier circuit in $CE$ configuration with $V_{CC} = 1 \text{ V}$,$R_c = 1 \text{ k}\Omega$,$R_b = 100 \text{ k}\Omega$,and $\beta = 100$,the value of the base current $I_b$ is:

For a given transistor,if $\alpha = 0.95$,find the common emitter current gain $\beta$.