Download AKTU B-Tech 1st Sem 2015-2016 NEE 101 Basic Electrical Engineering Question Paper

Download AKTU (Dr. A.P.J. Abdul Kalam Technical University (AKTU), formerly Uttar Pradesh Technical University (UPTU)) B-Tech 1st Semester (First Semester) 2015-2016 NEE 101 Basic Electrical Engineering Question Paper

Printed Pages : 5 1162 NEE-lOl
(Following Paper ID and Roll No. to be filled in your
T Answer Book)
R911 N0.
B.Tech.
(SEM. 1) THEORY EXAMINATION, 2015?16
BASIC ELECTRICAL ENGINEERING
[Time:3 hours] .. [Total Marks: 100]
SECTION-A
1. f Attempt all questions.All questions carry equal marks.
( 1 0 x 2=20)
(a) De?ne Bilateral & Unilateral Elements with
example.
(b) What will happen if the primary of a transformer
is connected to DC. supply?
(c) What are the advantages of wound rotor motors
over squirrel cage motors?
((1) State Superpostion Theorem & Norton?s Theorem.
43000 (1) P.T.O.

(e)
(f)
(g)
(h)
(i)
What happens when one phase of a delta connected
alternator is reversed?
What do?you mean by the term Resonance?
What is meant by Current magni?cation?
De?ne RMS value & Average value.
Define the terms: Permeability, Relative
permeability & Reluctance applied to magnetic
circuits.
How does magnetic circuit differ from Electric
circuit?
\
SECTION?B
Attempt any ?ve questions. All questions carry equal marks.
(10x5=50)
2. (a) HowNorton?s Theorem is equivalent to Thevnin?s
43000
Theorem? Also write the Limitations ofThevnin?s
Theorem and ?nd the voltage across load resistance
RL using Thevnin?s theorem When load resistance
$2kQ.
(2) NEE-IOI
1.5 kohm
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(b)
(C)
(d)
(6)
43000
Explain with a neat diagram, the constructional
features'and working of Dynamometer type
Wattmeter. Also write its merits & demerits.
Explain the principle ofoperation of a transformer.
Derive E.M.F. equation of Single phase
transformer.
What are the causes oflow power factor in supply
system? Discuss its effect & how power factor is
improved?
List the various Losses occurring in transformer
& the condition for maximum ef?ciency. In a 25
KVA, 2000/200 V transformer the iron & copper
losseiare 200 W & 400 W respectively. Calculate
the ef?ciency at half load & 0.8 power factor
lagging. detennine also the maximum ef?ciency
& the corresponding load.
C
(3) p.10.

(f)
(g)
(h)
Attempt any two parts of the following.
3. (a)
43000
What are the methods of power measurement in
3-phase Ac circuits? explain Two-Wattmeter
method for delta connected?l'oad.
Derive the expression for Generated E.M.F. in Dc
Machine. Explain the term Back E.M.F. when
applied to Dc motor. Brie?y explain what role Back
E.M.F plays in starting & running of motor.
Why is the Synchronous motor not self starting?
Explain the advantages & disadvantages along with
applications of Synchronous motor.
SECIION?C
(15X2?30)
Derive the expression of resonant frequency of
parallel R-L-C circuit. In series-parallel circuit A
& B are in series with C. The Impedances are:
ZA=4+j 3 Q , Z B=4-j5 Q , Z C=2+j8 Q. lfthe current
[c=(25+j0), calculate:
i) Branch Voltage
ii) Branch Currents
iii) Total Power
iv) Phasor Diagram
(4) NEE?lOl
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(b) Explain the working of 3-phase Induction motor.
(C)
43000
what is meant by slip? Explain Slip-Torque
characteristics of 3-phase Induction motor.
Obtain the relation between line & phase voltages
in balanced Star connected load system. Also draw
its Phasor diagram. A3 -phase, star connected
balanced load is supplied by 400 V, 50 Hz. The load
takes a leading current of 100 ?1 3 A & power 20
kW.Calculate power factor of load and Resistance
& Inductance per phase.
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(5) NEE-lO]