Draw a circuit diagram of C.E. transistor amplifier. Briefly explain its working and write the expression for (i) current gain (ii) voltage gain of the amplifier.

For a transistor amplifier, the voltage gain

Draw a schematic diagram of a step-up transformer . Explain its working principle . Deduce the expression for the secondary to primary voltage in terms of the number of turns in the two coils . In an ideal transformer , how is this ratio related to the currents in the two coils ?

Draw the circuit diagram of a common emitter transistor amplifier. Write the expression for its voltage gain. Explain , how the input and output signal differ in phase by 180^(@)

Draw a circuit diagram of n-p transistor amplifier in CE configuration. Under what condition does the transistor acts as an amplifier?

Draw a simple circuit of a CE transistor amplifier. Explain its working. Show that the voltage gain, A_(v) , of the amplifier is given by A_(v)= -(beta_(ac) R_(I))/(r_(i)) , where beta_(ac) is the current gain, R_(L) is the load resistance and r_(i ) is the input resistance of the transistor. What is the significance of the negative sign in the expression of the voltage gain ?

A common emiiter amplifier has voltage gain 50 and current gain is 25. The power gain of the amplifier is:

Draw the labelled circuit diagram of a common-emitter transistor amplifier : Explain clearly how the input and output signals are in opposite phase.

A transistor having alpha = 0.99 is used in a common base amplifier. If the load resistance is 4.5 kOmega and the dynamic resistance of the emitter junction is 50Omega the voltage gain of the amplifier will be

Give a circuit diagram of a common emitter amplifier using an n-p-n transistor. Draw the input and output wavefroms of the signal. Write the expression for its voltage gain.