Q1 What is an n-p-n transistor? Give its symbol and describe its working. Why is it more useful in comparison to p-n-p transistor? Solution

Q2 Describe briefly, with the help of a diagram, an n-p-n or p-n-p transistor. Define current gain for a transistor. Solution

Q3 Draw a labelled circuit diagram of an n-p-n transistor in a common-emitter configuration to study its characteristics. Solution

Q4 Drawing a labelled circuit diagram, explain how a p-n-p transistor can be used as an amplifier in common-emitter configuration? Derive expression for its voltage-gain. Solution

Q5 Draw a labelled circuit diagram of common-emitter type transistor (n-p-n or p-n-p) amplifier showing the biasing correctly Solution

Q6 Draw a labelled diagram of common emitter amplifier, showing waveforms of signal voltage and ourut voltage. Solution

Q7 Draw a circuit diagram for the common. transistor amplifier. What is meant by phase reversal? Solution

Q8 With proper labelling of the axes, draw the input and output characteristic curves of n-p-n transistor in common-emitter configuration.  Solution

Q9 Draw a labelled circuit diagram of a simple common- emitter amplifier. What is the phase angle between the input and output voltages? Solution

Q10 Figure below shows the circuit of an electronic device:



(i) Which electronic device: a rectifier, an amplifier or an oscillator does the circuit represent?
(ii) State where the input voltage is applied and where the output voltage is available.
(iii) Compare the output voltage of this circuit with its input voltage. Solution

Q11 What is an n-p-n transistor? Give its symbol and describe its working. Why is it more useful in comparison to p-n-p transistor? Solution