Download AKTU (Dr. A.P.J. Abdul Kalam Technical University (AKTU), formerly Uttar Pradesh Technical University (UPTU)) B-Tech 1st Semester (First Semester) 2016-2017 REE 101 Basic Electrical Engineering Question Paper
(F ollowing Paper ID and Roll No. to be ?lled in your
Answer Books)
B.TECH
Regular Theory Examination (Odd Sem-I), 2016-17
BASIC ELECTRICAL ENGINEERING- '
Time : 3 Hours 7 l I Max. Marks : 70
Not?: Attempt all sections. Answei' any data if found
missing.
SECTION-A
1. Attempt all the following parts. (7XZ=14)
a) Give two comparison between unilateral and
bilateral elements
b) Give two limitation of Thevenin?s theorem.
c) What will be the RMS value of voltage for
v = 416 sinwt waveform.
101/12/2016/25,800 (1) [9.10.
a)
e)
f)
g)
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In case two wattmeters are having same reading in a
tvsfo wattmeter method of power measurement what
wnll be the power factor of the circuit?
What do you mean by back emf in do motor.
Write emfequation of single phase transformer. '
Give two causes of Low. bower factor.
SECTION - B
2. Attempt any three front the following: (3X7=21)
3)
b)
State and Explain Kirhbho?"s Law. What are the
elimitations and applications of Kirchoff?s Law in
circuit theory explain.
What do you understand by ?Series Resonance? and
?Parallel Resonance?? What are the application of
tank circuits?
Derive relation between line and phase values' in delta
connected 3-phase balance system. A 3 phase
voltage source has a phase voltage of 120V and
101/12/2016/25,soo (2)
d)
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supplies star connected load having impedance of
24 + j36Q per phase.
Calculate
i) Line Voltage
ii) ?Line current
? iii) Tbtal 3-phase power supplied to the load.
Explain the working of induction type of single
phase energy meterwuth neat diagrams.
A 120 V dc shunt motor having an armature circuit
resist?nce of 0.2 Q a?nd ?eld circuit resistance of
60 g , draw a line current of 40 A at full load. The
brush voltage drop is 3V and rated full load speed is
? 1800 rpm.Ca1culate
i) The speed at h?lfload
ii) The speed at 125% offull load.
101/12/2016/25,800 ' (3) (p.110.
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? SECTION - C
Attempt any. five questions from the following
(5X7=35)
3. Using mesh analysis, ?nd the current 5 11,}, and I in the
following circuit of F ig.l ' h 3
A series ac circuit has a resistance of 15 Q and inductive
reaetarice of 10 Q . Calculate the value of a capacitor
which 18 connected across this series combination so that
system has unit power factor. The ?e uenc of ac s 1
is 50Hz q y ?pp y
101/12/201'6/25300 (4)
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A l-pahse 250/500 V transformer gave the following
results.
Open circuit test 250V, 1A, 80W (LV. side)
Short circuit test 20V, 12A, 100w (H.V.Side)
Calculate the equivalent cireuit parameters and show them
on an equivalent circuit.
i)
Explain why the hysteresis less and eddy current
loss occur in a transformer. Explain how these losses
canbe reduced in a transformer. (4)
What do you understand by the ef?ciency of a
transformer? Deduce the condition for maximum
ef?ciency. . (3)
0 Explain B-H loop for magnetic circuit. (3)
An iron ting 10 cm mean diameter is made of round
irori rod 1 .50m in diameter of relative penneability
of 900 and has an air gap of 5mm in length. It has a _
winding of 400 turns. If the current through winding
is 3.4 amp. Determine: I
101/12/2016/25,800 (5)
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REE - 10]
. ' I 10. The indUCed emf between the slip-ring terminals of 3-.
a) mmf phase induction motor, when the rotor is stand still is
100V. The rotor windings are star connected and have
resistance and stand still reactance of 0.05 Q and 0.1 Q
per phase respectively. Calculate the rotor current and
? phase difference between rotor voltage and current at 4%
slip.
b) ? Flux in the ring
c) ?ux density in the ring
(1) Total reluctance of the circuit.
8. Explain three wattmeter method to measure 3- ? power
in a Y connected?load. Derive the phase angle in terms of
wattmeter reading and also draw phasor diagram also.
9. a) ? Explain the speed-torque ch?racteristics of dc shunt
and series motors.
b) Explain why a synchronous motor does not develop V
starting torque. '
c) Explain the working principle of three phase
induction motor.
I ' ' 101/12/2016/25300 (7)
101/12/2016/25,800 (6) . .
This post was last modified on 29 January 2020