Wednesday 1 May 2013

Kerala University B.Tech. Combined First and Second Semester Basic Electrical and Electronics Engineering Previous Questions 2008 Scheme


Combined First and Second Semester B.Tech. Degree Examination, May 2009
08-108 : BASIC ELECTRICAL AND ELECTRONICS ENGINEERING
(2008 Scheme)


Instructions : 1) Answer all questions from Part – A and three full questions from Part – B.
                       2) Choosing not more than one question from each Module.
PART – A
1. Explain Kirchoff’s Laws.
2. What is Lenz’s Law ? Explain.
3. Distinguish between Phase and Phase difference.
4. What is the principle of operation of transformer ?
5. Name eight substation equipment.
6. Differentiate between MCB and ELCB.
7. Draw V-I characteristics of P-N Junction Diode.
8. Draw the schematic of L.T. switch board.
9. What are energy efficient lamps ? Explain any one.
10. What are transducers ? Explain.


PART – B
MODULE – I
11. a) Solve for currents I1, I2 and I3 using mesh current method.
b) A magnetic circuit comprises three parts in series, each of uniform cross sectional
area. They are
a) a length of 80 mm and cross-sectional area 50 mm2
b) a length of 60 mm and cross-sectional area 90 mm2
c) an air gap of length 0.5 mm
A coil of 4000 turns is wound on part b and flux density in the air gap is
0.3 T. Assuming that all the flux passes through the given circuit and that
the μ r is 1300. Estimate the coil current to produce such a flux density.
12. a) Prove that in a purely inductive circuit average power consumed is zero,
when connected to a single phase a.c.
b) A capacitor of 8μ F takes a current of 1.0 A when the a.c. voltage applied
across it is 230 V. Calculate :
a) Frequency of applied volt.
b) The resistance to be connected in series with capacitor to reduce the current
in the circuit to 0.5 A at the same frequency.
c) The phase angle of the resulting current.
MODULE – II
13. a) Draw the block schematic of a nuclear power plant and explain.
b) What is the need for high transmission voltage ? Draw a typical power
transmission scheme.
14. a) What are the different protective devices used in electrical installations ? Explain
any one in detail.
b) Explain constructional details of single phase and 3-phase transformers.
MODULE – III
15. a) Explain the working of zener voltage regulator ?
b) Explain the action of shunt capacitor filter.
c) Describe the working of UPS with a neat block diagram.
16. a) Draw and explain the VI characteristics of SCR.
b) With the help of block diagram explain how to produce a 9V DC power
supply from 230 V, 50 Hz a.c. supply.
c) Explain the working principle of photodiodes and solar cells.

No comments:

Post a Comment