(a) Describe briefly the functions of the three segments of n-p-n transistor.
(b) Draw the circuit arrangement for studying the output characteristics of n-p-n transistor in CE configuration. Explain how the output characteristics is obtained.
OR
Draw the circuit diagram of a full wave rectifier and explain its working. Also, give the input and output wave forms.
 

(a) 
(i) Emitter : supplies the large number of majority carriers for current flow through the transistor
(ii) Base: Allows most of the majority charge carriers to go over to the collector. It is the very thin lightly doped central segment of the transistor.
(iii) Collector : collects a major portion of the majority charge carriers supplied by the emitter.

(b)
 
OR

For full wave rectifier, we use two junction diodes as shown in figure.
During first half cycle of input a.c. signal the terminal Si is positive relative to S and S₂ is negative, then diode Di is in forward biased and diode D₂ is reverse biased.
Therefore, current flows in D₁ not in D₂. In next half cycle, Si is negative and S₂ is positive
relative to S. Then D1 is in reverse biased and D₂ is in forward biased.
Therefore, current flows in D₂ not in D1.
Thus, for input a.c. signal the output current is a continuous series of unidirectional pulse.
The input and output wave forms are shown in the figure.