a) What is rectifier? With a neat sketch, explain the working of bridge rectifier. 5
b) Draw and explain the V-I characteristics of a pn junction. 5
a) A full wave rectifier uses two diodes, the internal resistance of each diode may be
assumed constant at 20 Ω The transformer r.m.s. secondary voltage from centre tap to each
end of secondary is 50 V and load resistance is 980 Ω Find :
(i)the mean load current (ii)The r.m.s. value of load current 5
b) What is zener diode? Explain how zener diode maintains constant voltage across the load. 5
a) Draw and explain the input and output characteristics of CE configuration. 5
b) Define α and β. Show that . 5
4.A transistor is connected in CE configuration in which collector supply is 8V and
the voltage drop across resistance connected in the collector circuit is 0.5V.
The value of If α=0.96, determine:
collector-emitter voltage ii. base current 10
Write short note on: 10
LASER diode ii. Transducer and its application
a) In a CB connection, α=0.95. The voltage drop across 2 Kresistance which is connected is 2V.Find the base current. 4
b) Draw and explain the constructional diagram of cathode ray oscilloscope. 6
a) Explain the operation of tank circuit with neat diagrams. 6
b) In a certain RC oscillator circuit the value of R=220 k and C=250 pF. Determine
the frequency of oscillations. 4
a) Explain the term calibration, accuracy and precision. 5
b) What are the different methods of measurement of flow. 5
a) What are the functions of filter circuit? Explain capacitor filter with a neat circuit diagram and waveforms (4 Marks)
b) The four diodes used in abridge rectifier circuit have forward resistance which may be considered at 1 Ω and infinite reverse resistance. The alternating supply voltage is 240 V r.m.s. and load resistance is 480 Ω calculate mean load current and power dissipated in each diode. (6 Marks)
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