CS/B.Tech (OLD)/SEM-2/EE-201/2013
2013
BASIC ELECTRICAL ENGINEERING
Time Allotted : 3 Hours Full Marks : 70
The figures in the margin indicate full marks.
Candidates are required to give their answers in their own words
as far as practicable.
GROUP – A
( Multiple Choice Type Questions )
1. Choose the correct alternatives for any ten of the
following : 10 × 1 = 10
i) In three-phase induction motor
a) 3-phase supply is to be given to the stator winding
and d.c. supply the rotor winding
b) only 3-phase supply is to be given to the stator
winding
c) 3-phase supply is to be given to both stator and
rotor winding
d) 3-phase supply is to be given to rotor winding.
ii) A 400 V, 50 Hz three-phase induction motor rotates at
1440 rpm on full-load. The motor is wounded for
a) 2 poles b) 4 poles
c) 6 poles d) 8 poles.
iii) The slip of 400 V, 3-phase, 4-pole induction motor when
rotating at 1440 rpm is
a) 2% b) 3%
c) 4% d) 5%.
iv) A sinusoidal voltage is represented as
v =141.4 sin(314.18t -
).Its rms value of voltages,
frequency and phase angle are respectively
a) 141·42 V, 314·16 Hz, 90°
b) 100 V, 100 Hz, – 90°
c) 87·92 V, 56 Hz, 90°
d) 200 V, 50 Hz, – 90°.
v) The direction of current in an a.c. circuit is
a) always in one direction
b) varying from time to time
c) unpredictable
d) from positive to negative.