107 BEE&BEC

BTECH DEGREE MODEL EXAMINATION APRIL 2007

BASIC ELECTRICAL ENGINEERING & ELECTRONICS

Time:3 Hrs Max marks: 100

ELECTRICAL

PART A

1. a) State and explain Kirchoff’s law.

b) Define RMS, average and peak value of ac. What is form factor?

c) State and explain Faraday’s law.

d) State and explain Coulomb’s law.

e) How can we convert a galvanometer to ammeter?

PART B

2. a) State and explain super position theorem.

b) Give a suitable numerical example for super position theorem

3. a) Define 1) capacitance 2) charge 3) potential. Derive an equation b/w them.

b) Capacitors 4.2 micro Farad and 2.8 micro Farad are connected in series with another

capacitor. The effective capacitance is 0.9 micro Farad. If the group is connected

across 500V dc, calculate 1) capacitance of third capacitor 2) charge 3) voltage

across each capacitor.

c) Explain Norton’s theorem and derive the equation.

PART C

4. a) Explain self induction and mutual induction.

b) Explain the working principle of energy meter.

c) Show that line to line voltage of a 3 phase system is 1.732 times Vph. Draw the

voltage phasor diagram for ABC sequence.

OR

5. a) An inductor of 20 ohm resistance and 0.1 H inductance is connected in series with a

non inductive resistor 50 ohm. They are supplied from 230V 50Hz. Find the current

voltage and power factor of the circuit.

b) Resistance of 20 ohm, inductance of 0.2 H and capacitance of 100 micro Farad is

connected in series across 220V 50Hz mains. Determine 1) Impedance 2) current

3) voltage across R, L & C 4) Power in Watts and VA 5) power factor angle of lag.

ELECTRONICS

PART D

6. a) Differentiate b/w avalanche and zener breakdown.

b) Explain the term modulation and need for it in communication.

c) What is a transducer? What are different classes of transducer?

d) What is rectification? What are the different types of rectification?

e) What are Lissajeous pattern? How they are used in phase measurement.

PART E

7. a) Draw the block diagram of CRO & explain each block briefly.

b) Compare performance of AM & FM.

OR

8. a) Write the method to measure pressure, velocity, vibration & temperature .

b) What is demodulation? Draw & explain the ckt for AM reception.

PART F

9. a) Draw the V-I characteristics of Zener diode.

b) What is ripple factor& how can it reduce.

c) Distinguish b/w electron& hole.

OR

10.a) Explain the working of FET .

b) Explain the operation of npn transistor.

c) Draw the characteristics of UJT & explain it.

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