Anna University Chennai 2005 B.E ELECTRICAL ENGINEERING - Question Paper

Code: A-10 Subject: ELECTRICAL ENGINEERING
Time: three Hours Max. Marks: 100
NOTE: There are 11 ques. in all.
ques. one is compulsory and carries 16 marks. ans to Q. 1. must be written in the space given for it in the ans book supplied and nowhere else.
ans any 3 ques. every from Part I and Part II. every of these ques. carries 14 marks.
Any needed data not explicitly given, may be suitably presumed and said.
Q.1 Choose the accurate or best option in the following: (2x8)

a. The 2 windings of a transformer is
(A) conductively linked. (B) inductively linked.
(C) not linked at all. (D) electrically linked.

b. A salient pole synchronous motor is running at no load. Its field current is switched off. The motor will
(A) come to stop.
(B) continue on to run at synchronous speed.
(C) continue on to run at a speed slightly more than the synchronous speed.
(D) continue on to run at a speed slightly less than the synchronous speed.

c. The d.c. series motor should always be started with load because
(A) at no load, it will rotate at dangerously high speed.
(B) it will fail to begin.
(C) it will not develop high starting torque.
(D) all are actual.

d. The frequency of the rotor current in a three phase 50 Hz, four pole induction motor at full load speed is about
(A) 50 Hz. (B) 20 Hz.
(C) two Hz. (D) Zero.

e. In a stepper motor the angular displacement
(A) can be precisely controlled.
(B) it cannot be readily interfaced with micro computer based controller.
(C) the angular displacement cannot be precisely controlled.
(D) it cannot be used for positioning of work tables and tools in NC machines.
f. The power factor of a squirrel cage induction motor is
(A) low at light load only.
(B) low at heavy load only.
(C) low at light and heavy load both.
(D) low at rated load only.
g. The generation voltage is usually
(A) ranging from 11 KV and 33 KV. (B) ranging from 132 KV and 400 KV.
(C) ranging from 400 KV and 700 KV. (D) None of the above.
h. When a synchronous motor is running at synchronous speed, the damper winding produces
(A) damping torque.
(B) eddy current torque.
(C) torque aiding the developed torque.
(D) no torque.
PART I

Earning:   Approval pending.