The base current is $100 \mu A$ and the collector current is $3 \text{ mA}$. $A$ change of $20 \mu A$ in the base current results in a change of $0.5 \text{ mA}$ in the collector current. The value of $\beta_{ac}$ is:

In a common emitter transistor amplifier,the load resistance is $6.5 \text{ k}\Omega$ and the input resistance is $1.3 \text{ k}\Omega$. If the current gain is $78$,the voltage gain is:

Which of the following regions of transistors are,respectively,heavily doped and lightly doped?

When a transistor is used as an amplifier in common emitter configuration,which of the following statements are correct?
$(1)$ The base-emitter junction is forward-biased.
$(2)$ The base-emitter junction is reverse-biased.
$(3)$ The input signal is connected in series with the biasing voltage to the base-emitter junction.
$(4)$ The input signal is connected in series with the biasing voltage to the base-collector junction.

In a $CE$ transistor amplifier,there is a current and voltage gain associated with the circuit. In other words,there is a power gain. Considering power as a measure of energy,does the circuit violate the law of conservation of energy?

In a common base mode of a transistor,the collector current is $5.488 \ mA$ for an emitter current of $5.60 \ mA$. The value of the base current amplification factor $(\beta)$ will be