Mumbai University Previous year question papers
IV Sem Electronics Examination Dec 2012
Electronic and Electrical Measuring Instruments and Machine
N.B.: (1) Question No.1 is compulsory and solve any four questions out of remaining six questions.
(2) Assume suitable data if necessary and mention that assumption while solving that question. .
(3) Figures to the right indicate full marks.
1. Answer any four :- 20
(a) Define sensitivity of an analog instrument. For PMMC instrument with- FSD = 100 mA find sensitivity.
(b) What is Meggar _?Explain its working.
(c) For ADC, define resolution. Give suitable example.
(d)~Explain the working p’rinciple of DC Motor.
(e) Explain the function of delay Iirie in os”cilloscope.What are the .types of delaylines?
2.(a) What is intensity modulation? For what purpose it is used? Can phase and frequency be measured using intensity modul~tion ?
(b) What is Q meter? Explain anyone of the types of Q meter with the help of circuit diagram.
3. (a) Draw and explain Kelvin’s Bridge .. 10
(b) Explain the operating principle of 3-phase induction motor. 10
4. (a) Draw and explain the block diagram of digital storage oscilloscope. 10
(b) Explain R-2 R ladder technique of digital to analoge converter. 10
5.(a) Draw and explain anyone of the types of electronic voltmeter. State its two advantages over analog voltmeter.
(b) Explain digital phase meter using flip flop. Draw relevant wavf\forms at each point in a block diagram to illustrate.
6.(a) Explain Schering bridge for measurement of capacitance. Derive the equation of unknown capacitance at balanced condition.
(b) What is energy meter? Draw its constructional view and explain. 10
7.Write short notes on (any two) :- 20
(a) Variable reluctance stepper motor.
(b) A. F. signal generator
(c) Digital frequency meter