BSPHCL JR Engineer Syllabus JE Electrical Exam Pattern. bsphcl.bih.nic.in

1. Written Exam
2. Personal Interview.

Therefore, to helps the applicants in starting their preparation we have provided the General Syllabus which is a need for all the Post in this Notification.

Exam Type	Topics
Objective Type	General Knowledge
	Aptitude
	Reasoning
	General English
	Concerned Subjects

Exam pattern

The BSPHCL officials have not yet released the Exam pattern for the BSPHCL Junior Electrical Engineer exam. But, without exam pattern, the preparation is not easy. So, for the convenience of the candidates, we have provided the exam pattern which is given in the previous years. So, we hope this will help you in the exam preparation. We will update the exact exam pattern as soon as the officials release. So, No need to waste your valuable time. Start your preparation as early as possible. Use the JEE, JE study material provided on our site. Download the BSPHCL JEE Previous papers from our site.

SL. NO	Exam Type	Topics Included
1.	Objective Type	General Knowledge
2.		Quantitaticve Aptitude
3.		Reasoning
4.		General English
5.		Concerned Subjects

BSPHCL JEE Syllabus for General Knowledge:

History.

Heritage.

Tourism.

General Science.

Polity.

Chemistry.

Geography.

Physics.

Art & Culture.

Indian Constitution.

Literature.

Biology

Governance System

BSPHCL JEE Syllabus for Reasoning:

Logical Reasoning.

Blood Relations.

Syllogism.

Input Output.

Data Sufficiency.

Coded Inequalities.

Seating Arrangement.

Coding Decoding.

Alphanumeric Series.

Ranking/Direction/Alphabet Test.

PuzzleTabulation also.

Quantitative Aptitude for BSPHCL JEE SyllabuS

Simplification.

Ratio & Proportion, Percentage.

Number Systems.

Profit & Loss.

Mixtures & Alligations.

Simple Interest & Compound Interest & Surds & Indices.

Work & Time.

Time & Distance.

Mensuration – Cylinder, Cone, Sphere.

Sequence & Series.

Permutation, Combination & Probability.

Data Interpretation also.

General Awareness BSPHCL JEE Syllabus:

Current Affairs

Summits.

Books & Authors.

Awards.

Sports.

Defence.

National.

Appointment.

Obituary

International also.

General Science Syllabus:

Physics.

Chemistry.

Biology.

Environmental Science etc.

Hence, check the above topics for better preparation. As a result, the Candidates can get better Marks .

BSPHCL JEE ENGINEERING Syllabus(SIMILAR SYLLABUS RAJASTHAN,WEST BENGAL ,UP SSC JEE ENGG) and Bihar State Power Holding Corporation Ltd JE, Asst It Manager and other Posts Exam pattern

1.Electrical Branch

AC Fundamentals.

Utilization of Electrical Energy.

Power Systems.BSPHCL JEE ENGINEERING Syllabus(SIMILAR SYLLABUS RAJASTHAN,WEST BENGAL ,UP SSC JEE ENGG) and Bihar State Power Holding Corporation Ltd JE, Asst It Manager and other Posts Exam patternBSPHCL JEE ENGINEERING Syllabus(SIMILAR SYLLABUS RAJASTHAN,WEST BENGAL ,UP SSC JEE ENGG) and Bihar State Power Holding Corporation Ltd JE, Asst It Manager and other Posts Exam pattern

Power Electronics & Drives also.

Network Theory.

Electrical Machines also.

Basic Electrical Engineering Concepts.

Analog and Digital Electronics also.

Magnetic Circuit.

Estimation and costing.

Measurement and measuring instruments also.

Basic Electronics etc.

2.For Electronics BranCH

Basics of Circuits and Measurement Systems.

Analog Electronics.

Transducers, Mechanical Measurement and Industrial Instrumentation also.

Electrical and Electronic Measurements.

Digital Electronics.

Control Systems and Process Control also.

Analytical, Optical Instrumentation.

Signals, Systems, and Communications

BSPHCL JEE, IT Manager Recruitment Details

BSPHCL (Bihar State Power Holding Company Limited

Jr Electrical Engineer, Jr. Engineer, Asst IT Manager, Asst Operator, etc

Bihar state Power Holding Company limited in short we referred as BSPHCL is a government organization works under Bihar State Electricity Board. BSPHCL has five Subsidiaries and it is the responsible body for supply and distribution of power in the state. As per 2012 statistics more than 15000 of employees are working in this organization. Every year to fill empty vacancies if any found in the subsidiaries and in BSPHCL the management releases employment notifications.

No of Posts: 1033 vacancies.

Job Location: Bihar,

Last Date: 1st October 2016.

Mode of Application: Online.

Official Website: bsphcl.bih.nic.inBSPHCL JEE ENGINEERING Syllabus and PREVIOUS YEAR PAPER (SIMILAR SYLLABUS RAJASTHAN,WEST BENGAL ,UP SSC JEE ENGG) and Bihar State Power Holding Corporation Ltd JE, Asst It Manager and other Posts Exam pattern

previous year paper

1. SCR is the solid state equivalent of

a. Transistor

b. Thyratron

c. Vacuum
diode

d. Crystal diode

Answer: B

2.
With gate open, if the supply voltage exceeds the breakover voltage of SCR,
then SCR will conduct

a. False

b. True

c. For DC

d. For AC

Answer: B

3.
The SCR is turned off when the anode current falls below

a. Forward
current rating

b. Break over
voltage

c. Holding
current

d. Latching
current

Answer: C

4.
In a SCR circuit, the angle of conduction can be changed by changing

a. Anode
voltage

b. Anode
current

c. Forward
current rating

d. Gate
current

Answer: D

5.
The normal way to close a SCR is by appropriate

a. Gate
current

b. Cathode
current

c. Anode
current

d. Forward
current

Answer: A

6.
An SCR has ......PN junctions

a. Two

b. Four

c. Three

d. One

Answer: C

7.
If gate current is increased, the anode-cathode voltage at which SCR closes
is.....

a. Increased

b. Decreased

c. Maximum

d. Least

Answer: B

8. A
conducting SCR can be opened by reducing ..... to zero

a. Supply
voltage

b. Grid
voltage

c. Grid
current

d. Anode
current

Answer: A

9.
With gate open, a SCR can be turned-on by making supply voltage....

a. Minimum

b. Reverse

c. Equal to
cathode voltage

d. Equal to
breakover voltage

Answer: D

10.
If firing angle in a SCR rectifier is increased, output is....

a. Increased

b. Maximum

c. Decreased

d. Unaffected

Answer: C

11.
A SCR is a ...switch

A. Two
directional

B.
Unidirectional

C. Three
directional

D. Four
directional

Answer: B

12.
The anode of SCR is always maintained at........potential with respect to
cathode

A. Positive

B. Zero

C. negative

D.
Equipotential

Answer: A

13.
IF the chopper switching frequency is 200Hz and Ton time is 2ms, the duty cycle
is

A. 0.4

B. 0.8

C. 0.6

D. None of the
above

Answer: A

14.
Speed control of induction motor can be effected by varying

A. Flux

B. Voltage
input to stator

C. Keeping
rotor coil open

D. None of the
above

Answer: B

15.
In a Dc motor if the field coil gets opened, the speed of the motor will

A. Decrease

B. Come to
stop

C. Increase

D. None of the
above

Answer: C

PREVIOUS YEAR PAPER

1.
Find
the Fourier sine transform of f(x), where

f(x)
= f(x) 1,0<x<a

{ 0, x>a

(a)
√2/p (cos st / s)

(b)
√2/p (1 - cos as / s) (Ans)

(d) None of
these

2. A random variable X with uniform
density in the interval 0 to 1 is Quantized as follows:

If 0 ≤ X ≤ 0.3, x_q=
0

If 0.3 ≤ X ≤ 1, x_q=
0.7

Where X_qis the quatized value of x

The root mean square value of the quantization noise is

(a) 0.573

(b) 0.198 (ans)

(d) 0.266

Solution
: Since
it is uniform as

x_q= 0 in the range 0≤x≤0.3

x_q= 0.7 in the range 0.3≤x≤1

The square mean value is

¥

s² = ∫ (x - x_q)² f
(x) dx

      -¥

       ₁

    = ∫ (x - x_q)² f
(x) dx

      ⁰

     _{0.3
0.1}

    = ∫ (x - 0)² f (x) dx + ∫ (x - 0.7)² f (x) dx

      _{0
0.3}

_{0.3
1}

    = [x³/3]    + [x³/3
+ 0.49 x - 1.4]


_{0
0.3}

or s² = 0.039

The root mean square quantization noise

RMS = √s²

= √0.039 = 0.198

3. Choose the correct one from among
the alternatives A, B, C, D after matching an item from Group 1 with the most
appropriate item in Group 2.

Group 1	Group 2
1 : FM	P : Slope overload
2 : DM	Q : m Law
3 : PSK	R : Envelope detector
4 : PCM	S : Capture effect
	T : Hilbert transform
	U : Matched filter

(a) 1 - T,     2 -
P,        3 -
U,         4 - S

(b) 1 - S,
2U,           3 -
P,         4 - T

(d) 1 - U,    2 -
R,         3 -
S,         4 - Q

Solution
: FM
--- Capture effect --- Receives only strong signal

DM ----
Slop over load Noise

PSK ---
Matched filter

PCM - m law
- Non linear quantization by using Companding with a law

V =
log (1 + m
|M|)

log (1 +m )

4. There analog signals, having
bandwidth 1200 Hz, 600 Hz and 600 Hz, are sampled at their respective Nyquist
rates, encoded with 12 bit words, and time division multiplexed. The bit rate
for the multiplexed signal is

(a) 115.2 kbps

(b) 28.8 kbps

(d) 38.4 kbps

Solution
: The
three analog Signals having BW 1200 Hz, 600Hz and 600 Hz are sampled at their
respective Nyquist rate i.e. at 2400, 1200, 1200 sample/sec respectively.

The total
of (2400 + 1200 + 1200) = 4800 sample/sec

The Bit
rate = n. f_s= (4800 sample/sec) x 12 = 57.6 Kbps

Where n =
number of bit in a symbol

5.
Find the correct match between group 1 and group 2.

Ground I

P - [1 + km (t)] A sin (w_ct)

Q - km (t) A sin (w_ct)

R - A sin [ w'_c + k]'_-¥m (t)
dt

S - A sin [w_ct + k '∫_-¥m (t) dt]

Solution
:

Group II

W - Phase modulation

X - Frequency modulation

Y - Amplitude modulation

Z - DSB-SC modulation

P
Q
R        S

(a) Z
Y
X        W

(b) W
X
Y        Z

(d)   Y
Z
W        X (ans)

Solution
: The correct match is given below

[1 + km (t)] A sin (w_ct)	Amplitude modulation
km (t) A sin (w_ct)	DB-SC modulation
A sin [w'_c+ k]'_-¥ m (t) dt	Phase modulation
A sin [w_ct + k ^'∫_-¥ m (t) dt]	Frequency modulation

6. Which of the following analog
modulation scheme requires the minimum transmitted power and minimum channel
bandwidth?

(a) VSB

(b) DSB-SC

(d) AM

Solution
:
VSB → f_m + f_c

DBS - SC → 2 f_m

SSB → f_m

AM → 2 f_m

Thus SSB
has minimum bandwidth and it required minimum power i.e. 17% as compared to AM.

7.
A device with input x(t) and output y(t) is
characteristic by : y (t) = x²(t). An FM signal with frequency
deviation of 90 KHz and modulation signal bandwidth of 5 KHz is applied to this
device. The bandwidth of the output signal is

(a) 370 KHz (ans)

(b) 190 KHz

(d) 95 KHz

Solution
: In
present case

∆f =
90; f_m = 5

β = [∆f
/ f_m] = [90/5] = 18

FM equation

A cos [w_ct + β = sin w_mt]

= A
cos [w_ct + 18 sin
w_mt]

y(t) = x² (t) = A²cos²[w_ct +
18 Sin w_mt]

Note : Cos²q = [1 + Cos2q] / 2

If there is change in frequency the modulation index also changes in
same ratio

y(t) = A²[(1/2)
+ (1/2) Cos {2w_ct +
36Sin w_mt}]

y(t) =[(A²/2) + (A²/2) Cos {2w_ct
+ 36Sin w_mt}]

After the device,

β_(new) = 36 = [∆f_(new) / f_m]

∆f_(new)
=36 x 5 = 180

By carson's
rule

Bandwidth = 2(∆f
+ f_m)

= 2 (180 + 5)

Bandwidth = 370 kHz

9.
A carrier is phase modulated (PM) with frequency deviation of 10 KHz by a
single tone frequency of 1 KHz. If the single tone frequency is increased to 2
KHz, assuming that phase deviation remains unchanged, the bandwidth of
the PM signal is

(a) 21 kHz

(b) 22 kHz

(d) 44 kHz (ans)

Solution
: ∆f
= 10 KHz f_m_(new)= 2 KHz

f_m= 1 KHz

By carson's Rule

BW = 2 (∆f
+ f_m) = 2 (10 + 1) = 22
KHz

∆ f_(new)= 2 x 10 = 20

BW_(new)= 2 (20 + 2) = 44 kHz

10
If A and B be the set and A^c and B^c
denote the complements of the sets. A and B, then set (A -
B) È (B - A) È (A Ç B) is equal to

(a) A
È B (Ans)

(b) A^c
È B^c

(d) A^c
Ç B^c

11
Let
G = G(V, E) has five vertices, then the maximum number of m
of edges in E, if G is a multigraph ?

(a) 5

(b) 2

(d) Finite
or infinite (Ans)

12
How
many straight line can be drawn through 10 points on a circle ?

(a) 10

(b) 20

(d)
Infinite

13
. The
Fourier transform of unit step function u(t) is

(a) 1

(b) pd(w)

(d) pd(w) +
1/jw

14.
The
value of the integral ∫     e^{-2(x - t)} d(t -
2) dt is


-∞

(a) e^{-2(x
- 2)} (Ans)

(b) e^{2(x
- 2)}

(d) e^{2(x
+ 2)}

15.
The
uint of Ñ x H is

(a) A

(b) A/m

(d) A-m

PREVIOUS YEAR PAPER

ELECTRICAL ENGINEERING

PRACTICE SET- 2

Q.1:- Two materials have resistance temperature coefficients of 0.004 and 0.0002 respectively at a given

temperature. In what ratio should the wires made of these materials be connected in series so as to have

an overall temperature coefficient of 0.002?

(a) 1:2 (b) 2:3 (c) 9:10 (d) 15:16

Q.2:- Consider the two fields,

E = 120 cos (10⁶ t- x) V / m

And

H = A cos (10⁶ t- x) / m.

The values of A and β which will satisfy the Maxwell’s equation in a linear isotropic, homogeneous,

loss-less-medium with = 8 and

= 2 will be

A (in A / m) β (in rad / m)

(a) 1 0.0105

(b) 1 0.042

(d) 2 0.042

Q.3:- A chopper operating at a fixed frequency is feeding an R-L load. As they duty ratio of the choppe is

increased from 25% to 75%, the ripple in the load current.

(a) Remains constant.

(b) Decreases, reaches a minimum at 50% duty ratio and then increases.

(d) Keeps on increasing as the duty ratio is increased.

Q.4:- A sinusoidal waveform, when observed on an oscilloscope, has a peak to peak amplitude of 6cm. If

the vertical sensitivity setting is 5 V / cm, the rms value of the voltage will be

(a) 10.6 V (b) 11.1 V (c) 12.6 V (d) 15 V

Q.5:- Which of the following is an example of an open-loop system?

(a) Household refrigerator.

(b) Respiratory system of an animal.

(d) Execution of a program by a computer.

Q.6:- A binary tree T has n leaf nodes. The number of nodes of degree 2 in T is

(a) (a) n (b) n – 1

(b) (c) n (d) 2

Q.7:- An n-channel silicon ( = 1.1 eV) MOSFET was fabricated using n⁺ poly silicon gate and the threshold

voltage was found to be 1 V. Now, if the gate is changed to p⁺ poly-silicon, other things remaining the

same, the new threshold voltage should be

(a) –0.1 V (b) 0 V (c) 1.0 V (d) 2.1 V

Q.8:- Scintillation is

(a) Variation of physical dimensions under the influence of magnetic field.

(b) Deionization of gases under low pressures.

(d) Change in dielectric constant of substances with change in humidity.

Q.9:- Which of the following statements is true?

(a) ROM is Read /Write memory.

(b) PC points to the last instruction that was executed.

(d) All instructions affect the flags.

Q.10:- In which range the cost of a synchronous motor is likely to be comparable to the cost of induction

motor?

(a) Low H.P., high speed.

(b) High H.P., low speed.

(d) Low H.P., low speed.

Q.11:- which one of the theories given below is related to the theory of the thermocouple?

(a) Piezoelectric effect (b) Skin effect (c) See back effect (d) Faraday’s Law

Q.12:- For the purpose of analysis exact equivalent circuit of a transformer is usually replaced by an

approximate equivalent circuit. In doing so errors introduced due to winding copper loss and core loss are

of differential nature. Due to this the analysis by approximate equivalent circuit gives fairly satisfactory

results. Under the circumstance, which one of the following is correct in respect of losses referred to

approx. Equivalent circuit?

(a) This accounts for somewhat greater primary winding copper loss and more cores less core loss.

(b) This accounts for somewhat lesser primary winding copper loss and more core loss.

(d) This accounts for somewhat lesser secondary winding copper loss and more core loss.

Q.13:- Consider the following statements: In a 3-phase induction motor connected to a 3-phase supply; if

one of the lines suddenly gets disconnected, then the

1. Motor will come to a standstill.

2. Motor will continue to run at the same speed with line current unchanged.

3. Motor will continue to run at a slightly reduced speed with increased line current.

4. Rotor currents will have both sf and a (2-s) f component frequency where s is the slip and f is the

supply frequency.

Of these statements:

(a) 1 and 4 are correct

(b) 1 and 2 are correct

(d) 2 and 3 are correct

Q.14:- While a 2-phase ac servomotor is in operation, if the voltage across the control field winding

becomes zero, then the motor has a tendency to run as a single-phase induction motor. To prevent this

(a) rotor having high mass moment of inertia is used for such a motor

(b) drag cup type of light rotor with high rotor resistance is preferred

(d) The number of turns in the control field winding used is less than the main reference wingding.

Q.15:- The inertia constant of a 100 MVA, 11 KV water wheel generators is 4. The energy stored in the rotor

at the synchronous speed is

(a) (a) 400 MJ (b) 400 KJ

(b) (c) 25 MJ (d) 25 KJ.

Q.16:- A separately excited dc generator is feeding a shunt motor. If the load torque on the motor is halved

approximately.

(a) Armature currents of both motor and generator are halved.

(b) Armature current of motor is halved and that of generator is unaltered.

(d) Armature currents of both motor and generator are unaltered.

Q.17:-Which variety of coal has lowest calorific value?

(a) Steam coal

(b) Bituminous coal

(d) Anthracite

Q.18:- The Current through an electrical conductor is 1 ampere when the temperature of the conductor is

0°C and 0.7 ampere when the temperature of the conductor is 1200°C must be

(a) 0.08 A (b) 0.16 A (C) 0.32 A (d) 0.64 A

Q.19:- The velocity of a travelling electrmagnetic wave I freee space is given by

(a) μ₀ ε₀ (b) √ ₀ ₀ (c)

√ ₀ ₀ (d) ₀ ₀

Q.20:- When a thyristor is negatively blased

(a) all the three junctions are negatively blased .

(b) outer junctions are positively blased and the inner junction is negatively biased.

(d) the junction near the anode is negatively biased and the one near the cathode is positevely

biased.

Q.21:- In the two-wattneter nethod of neasurung power in a balanced threee-phase circuit, one wattmeter

shows zero and thr other positve maximum. The lad powe factor is

(a) zero (b) 0.5 (c) 0.866 (d) 1.0

Q.22:- If the unit step response of a system is a unit impusle function, then the transfer function of such a

system will be

(a) 1 (b) 1/s (c) s (d) 1 / s²

Q.23:- The probability that a number selected at random between 100 and 999 (both inclusive will not

contain the digit 7 is

(a) 16/25 (b) (9/10)³ (c) 27/75 (d) 18/25

Q.24:- In the ciruit shown in the figure, N is a fintie gain amplifier with a gain of k, a very input impendance,

and a very low output impedance. The input impendance of the feedback amplifier with the feedback Z

connected, as shown will be

(a) Z (1-1 / k)

(b) Z (1-d)

(d) Z (1-k)

Q.25:- A satellite carrying antenna system, transmitter, receiver and power supply is known as

(a) geostationary satellite

(b) orbital satellite

(d) passive satellite

Q.26:- In a virtual memory system, the address space specified by the address lines of the CCPU must than

the secondary storage size.

(a) smaller, smaller

(b) smaller, larger

(d) larger, larger

Q.27:- Wires are made by

(a) spinning

(b) rolling

(d) turning

Q.28:- Based on the cohesive energy of an ionic solid, which of the following is not a property of the ionic

solid?

(a) It forms relatively stable and hard crystals

(b) It is a poor electric conductor

(d) None of the above.

Q.29:- If the wave-form of the voltage impressed on the primary of a Y-Δ bank contains a 5th harmonic, the

wave-forms of the resultant voltages of primary and the secondary would be

Primary Secondary

(a) Peaked peaked

(b) Peaked flat-topped

(d) Flat-topped flat-topped

Q.30:- In a self-excited induction generator, to keep the frequency of generated voltage constant with the

increase in load the speed of the induction machine should be

(a) Increased.

(b) Decreased.

(d) Maintained more than the rated synchronous speed.

Q.31:- The speed of a universal motor can be controlled by

(a) introducing a variable resistance in series with the motor

(b) tapping the field at various points

(d) all of the above steps

Q.32:- A large a.c. generator, supplying to n infinite bus, has a sudden short-circuit occurring at it’s the

voltage behind the transient reactance to remain constant immediately after the fault, the acceleration of

the generator rotor is

(a) inversely proportional to the moment of inertia of the machine

(b) inversely proportional to the square of the voltage

(d) Directly proportional to the short-circuit power.

Q.33:- An electric train employing a dc series motor is running at a fixed speed, when a sudden slight drop

in the mains voltage occurs. This would result in

(a) drop in speed and rise in current

(b) rise in speed and drop in current

(d) Drop in speed with current unaltered.

Q.34:- Ball mill is used in power plants using

(a) multi-stage expansion

(b) water softening

(d) Pulverized fuel firing

Q.35:- In the circuit shown in figure, 1 = 10 micro-amperes. The value of resistance is

(a) 1 kilo-ohm

(b) 10 kilo-ohm

(d) 1 Mega-ohm

Q.36:-The equation of a plane wave may be written as (with) usual symbols

(a) ²(

² = ²

(b) ²(

² = ²

(d) ²(

² = ²

Q.37:- A single-phase voltage source square-wave inverter feeds pure inductive load. The waveform of the

load current will be

(a) Sinusoidal (b) rectangular (c) trapezoidal (d) triangular

Q.38:- A 35V dc supply is connected across a resistance of 600 ohm in series with an unknown

resistance . A voltmeter having a resistance of 1.2 k-ohms reads 5V. The value of resistance will be

(a) 120 ohm (b) 400 ohm (c) 1.8 k-ohm (d) 2.4 k-ohm

Q.39:- When a unit-step input is applied, a second order under damped system has a peak overshoot of OP

occurring at . If another step input equal in magnitude to the peak overshoot OP is applied at. t

= then the system will settle down at

(a) 1 + OP (b) 1 – OP (c) OP (d) 1.0

Q.40:- Let R be a symmetric and transitive relation on a set A. Then

(a) R is reflexive and hence an equivalence relation

(b) R is reflexive and hence a partial order

(d) None of the above.

Q.41:- In a bipolar transistor at room temperature, If the emitter current is doubled, the voltage across its

base-emitter junction

(a) Doubles (b) halves (c) increases by about 20 mV (d) decreases by about 20 mV

Q.42:- layer has maximum ionic density of 3.5 x 10 electrons per cc. The critical frequency for this layer

will be

(a) 1.68 MHz (b) 400 MHz (c) 400 KHz (d) 40 KHz

Q.43:- An instruction used to set the carry Flag in a computer can be classified as

(a) Data transfer (b) arithmetic (c) logical (d) Program control

Q.44:- ‘Figure of Merit’ is used to

(a) compare the efficiency of the thermoelectric materials

(b) measure the extent of doping of intrinsic semiconductors

(d) None of the above.

Q.45:- A certain photoconductive cell is known to have a critical wave-length of 0.5 micrometer. Then the

minimum energy required to move an electron from the valence band to the conduction band is:

(a) 0.96 electric volt (b) 0.31 electron volt (c) 0.62 electric volt (d) 2.48 electron volts

Q.46:- A 50 Hz operation, a single-phase transformer has hysteresis loss of 200 W and eddy current loss of

100 W. Its core loss at 60 Hz operation will be

(a) 432 W (b) 408 W (c) 384 W (d) 360 W

Q.47:- Cogging and crawling are phenomena associated with

(a) cage induction machines and they are essentially the same

(b) squirrel cage induction machine, the former at a fraction of its rated speed and the latter during

starting

speed

(d) Wound rotor induction machines and they are reduced by skewing, chording and distribution of

windings.

Q.48:- Match List-1 (type of single-phase motor) with List-2 (type of appliance) and select the correct

answer using the codes given below the lists:

List-1 List-2

A. Permanent magnet type 1.Rocket

B. Shaded pole 2. Refrigerator compressor

C. Universal 3. Sewing machine

D. Capacitor shunt, capacitor run induction motor 4. Photocopying machine

Codes:

(a) A B C D

1 2 3 4

(b) A B C D

1 2 4 3

4 1 3 2

(d) A B C D

1 4 3 2

Q.49:- The fifth harmonic component of the induced voltage in 3-phase ac generator can be entirely

eliminated by using a winding pitch of

(a) 2 / 3 (b) 4 / 5 (c) 5 / 6 (d) 6 / 7

Q.50:- Consider the following drive systems:

1. Chopper fed dc series motor

2. Chopper fed dc shunt motor

3. Chopper fed permanent magnet dc motor

4. Brushless dc motor drive

5. Inverter fed 3-phase induction motor

6. Inverter fed 3-phase synchronous motor

For the development of a battery operated electric car the possible options are

(a) 1 , 3 and 5

(b) 2 , 4 and 6

(d) 1 , 4 and 5

Solution

1:- (c) Let the materials be in the ratio of k = x / y

∴ . × .

× = 0.002

∴ . . = 0.002

∴ . × . = 0.002

∴ 0.004k + 0.000 = 0.002

∴ 0.002k = 0.0018

∴ .

. =

Hence, the materials should be in the ratio 9:10.

2:- (d) E / H = , the characteristic impedance of the medium.

3:- (a) Load voltage =

= E = Ef

There are two ways to vary either by varying f or . Here frequency is fixed and is varied.

As the frequency is kept constant ripple remains constant.

4:- (a) Amplitude of the signal is × = 15 V.

∴ rms value is √ = 10.6 V.

5:- (d) Execution of a program by a computer is an example of an open-loop system.

6:- (b) It can be proved by induction that a strictly binary tree with ‘n’ leaf nodes will have a total number of

2n-1 nodes. So number of non-leaf nodes is (2n-1) –n = n-1.

7:- (c) 1.O V

8:- (c) Certain crystals such as zinc sulphide, sodium iodide, antracene and naphthalene, etc. produce a

brief flash of light each time they are struck by an alpha or beta or gamma particles. The production of a

flash of light by striking the crystals mentioned above, with alpha, beta or gamma rays, is called

scintillation.

9:- (c) Stack works on the principle of LIFO.

10:- (b) the cost of an induction motor increase disproportionately in high H.P. range and also as operating

speed reduces. It is, therefore, in this range where the cost of the two machines is comparable.

11:- (c) “An electromotive force results from a difference of temperature between two junctions of

dissimilar metals in the same circuit.”

This effect was first noted by Thomas Johanna See back. The difference of electric potential which results

from the difference in junction on temperatures is dependent upon the metals used, the temperatures of

the junction, and the intimacy of contact between the two metals. Such a combination of dissimilar metals,

when used to produce an emf, is called a thermocouple, and has many uses in the measurement of

temperature.

12:- (b)

‘Shall be slightly greater than and therefore, slightly greater core loss Current flowing through is now

somewhat less than and therefore reduced copper loss in it

Note: - If the shunt branch is shifted to 2-2’, then the answer would be (c). It depends on which

approximate circuit is used. The one given above is more common.

13:- (c) The motor will not stop. It will continue to run as a single phase motor with two phases of the

windings connected in series (for a star- connected) and third phase open; while for a delta – connected

motor, one phase of the winding and two other phases in series of the winding are in parallel. The field in

the air gap is pulsating which can be resolved into a forward rotating components. The rotor, therefore, has

both s f and (2 – s) f component frequencies.

14:- (b) Drag cup type of light rotor with high rotor resistance is preferred.

15:- (a) Inertia constant H

Mega joules of energy stored in the rotating mass of the alternator at

= ,

Thus, 4 =

∴ E = 400 MJ.

16:- (a) Since field winding currents of the two machines are not disturbed and the torque is proportional

to the product of armature current and field flux, when the torque reduced to half, the armature current in

both also reduces to half.

17:- (c) Lignite coal has lowest calorific value.

18: (b) Let be the temperature coefficient.

Then = Ro (1 + t)

Where is resistance at t° C and is resistance at 0°C

Assuming that for a given potential to 1 / R

We have

. = ( = 1 +. 100

0.7 amps,

∴ = 0.0043 ℃

The current I, at 1200°C is given by

= ( . ) = 1 +. 1200

= 1 + 0.0043 x 1200 = 6.16

∴ I = 1 / 6.16 = 0.16 amp.

19:- (c) A standard relation VO =

20:- (c) When a thyristor is negatively biased, outer junctions are negatively biased and the inner junction is

positively biased.

21:- (b) the wattmeter read

One ∝ cos(30 + )

Then other ∝ cos 30 −

Thus whenever load p.f. angle ϕ becomes 60° one of the watt meters would read zero.

∴ For the given condition the load p.f. is

Cos 60° = 0.5

22:- (c) Input r (t) = u (t) ∴ R (s) = 1 / s

Out put c (t) = (t) ∴ C (s) = 1

Transfer function = ( )

( ) = / s.

23:- (d) Probability that the unit digit is not 7 is 9 / 10. Probability that the tens digit is not 7 is 9 / 10.

Probability that the hundreds digit is not 7 is 8 / 9. So, probability that the unit digit is not 7 and the tens

digit in not 7 and the hundreds digit is not 7 is:

(9 / 10) (9 /10)(8 /9) = 18 /25.

24:- (d) From Miller’s theorem = Z / 1 – K.

25:- (c) The active satellite carries antenna system transmitter receiver and power supply. It works as an

active micro-wave repeaters, relay and signal to the receiving station either instantly or after storage in its

memory and waiting until the satellite faces the earth based receiving station.

26:- (c) Larger, smaller.

27:- (c) Wire-drawing process is used for making wires of various diameters.

28:- (d) the cohesive energy, which is the energy needed to take the solid apart into positive and negative

ions, is relatively high for ionic solids. Therefore, they should be poor electrical conductors since there are

no free elections available. They should be hard and stable with high vaporization temperatures and high

melting points.

29:- (b) Peaked- flat topped.

30:- (a) When a slip becomes negative, the induction machine acts as a generator, therefore, the rotor

speed should be more than the rated synchronous speed. Further, as the load increases, slip magnitude

should increase as the power output is approximately proportional to slip magnitude for small slips.

Therefore, speed will have to be increased.

31:- (b) It can be controlled by tapping the field at various points.

32:- (a) M =

M : Moment of inertia of the machine

² : Second time derivative of the load or the torque angle which turns out to be same

as rotor acceleration.

: Shaft power

: Electrical power output

Since ≈ 0 on occurrence of a short circuit,

We have ²

² =

33:- (d) In a series motor, the torque is approximately proportional to current squared. The train resistance

speed curve is such that there is very little increase in torque with speed; we can assume that torque

remains constant. Therefore, the armature current remains constant with increase in applied voltage, the

back emf reduces, which is achieved by a drop in speed.

34:- (d) Ball mill is used in power plants using pulverized fuel firing.

35:- (c) Let the current flow through resistance when – 12V Battery is removed. So,

= ×

Similarly current flow in resistance When + 12 V battery is removed. So,

= ×

Since the two voltages are in opposite directions, their currents will subtract. Hence,

× − ×

= 10 x 10

12(1000x1000+ ) – 12(470x1000+ )

10x 10 (1000x1000+ ) x(470x1000+ )

² + 1470x1000 – 16.6x10 =0

Solving for we have

= × ± ( × ) . × ⁹

10, 1000 ohms (rejecting the negative value)

36:- (a) One may arrive at the correct choice by comparing the two sides dimensionally. Since 1 / has the

dimension of velocity squared,

The pertinent choice is ²

² = ×²

37:- (d) The waveform of the load current will be triangular.

38:- (d) The voltage across is = 35 – 5 = 30V. The current in the circuit is

39:- (a) It will settle down at 1+ OP.

40:- (c) Let aRb. Since the relation is symmetric bRb. Since transitivity holds good, aRb and bRa implied aRa.

Also bRa implies aRa and bRb. If R has to be an equivalence relation, it has to be reflexive, i.e. for any x

belonging to A, xRx should hold good. So, R need not be reflexive and so R need not be and equivalence

relation.

For example, let a = (1, 2, 3)

Let R = {(1,2),(2,1),(1,1),(2,2)}

R is both symmetric and transitive but R is not reflexive as (3,3) is not present in R.

41:- (c) Its base-emitter junction increases by about 20 mV.

42:- (b) Critical Frequency, fc = 9 √

= 9 3.5 × 10⁶ × 10 = 16.839 MHz.

43:- (b) Arithmetic

44:- (a) “Figure of merit” is used to compare the efficiency of thermo-electric materials.

45:- (d) The minimum energy of a photon required to excite an electron from the valence band to the

conduction band is the forbidden energy gap of that semiconductor material. The relationship between the

wavelength of the photon and the energy gap is given by

= .

= energy gap = minimum energy required to move an electron from the valence band to the

conduction band, in electron volts. = Critical wavelength of the photon (micrometers).

1.24 = constant that arises from the Planck’s constant.

Substituting the given data,

= .

. = 2.48 electron volt.

46:- (c) If the operation of the transformer is at the same rms value of the voltage, then

Eddy current loss, = f² ²

Thus eddy current loss in not affected. And the total loss is 179.3+100=279.3W. This does

not tally with any of the given answers. Assume, the before that the flux density value is not

charge. Then

= 200 x =240 W

= 100 x ( )² = 144 W.

∴ Total loss = 384 W.

47:- (c) Cogging and crawling are phenomena associated with squirrel cage induction machine, the former

during starting and later at a fraction of its rated speed.

48:- (d) A – 1, B – 4, C – 3, D - 2.

49:- (b) Coil span factor for harmonic is

= Cos 1BSPHCL JEE ENGINEERING Syllabus and PREVIOUS YEAR PAPER (SIMILAR SYLLABUS RAJASTHAN,WEST BENGAL ,UP SSC JEE ENGG) and Bihar State Power Holding Corporation Ltd JE, Asst It Manager and other Posts Exam pattern

2 n ∈

Where ∈ is the angle by which the coil is short of full pitch?

= Cos 1

2 × 5 × (1 − ) = 0

Thus fifth harmonic component gets eliminated by using a coil pitch of 4/5.

50:- (a) 1, 3 and 5 are Correct.

Search This Blog

Tips Engineer Zone www.tipsengineerzone.in

BSPHCL JEE ENGINEERING Syllabus and PREVIOUS YEAR PAPER (SIMILAR SYLLABUS RAJASTHAN,WEST BENGAL ,UP SSC JEE ENGG) and Bihar State Power Holding Corporation Ltd JE, Asst It Manager and other Posts Exam pattern

BSPHCL JR Engineer Syllabus JE Electrical Exam Pattern. bsphcl.bih.nic.in

Exam pattern

BSPHCL JEE Syllabus for General Knowledge:

BSPHCL JEE Syllabus for Reasoning:

Quantitative Aptitude for BSPHCL JEE SyllabuS

General Awareness BSPHCL JEE Syllabus:

General Science Syllabus:

BSPHCL JEE, IT Manager Recruitment Details

Comments

Post a Comment

Popular posts from this blog

Induction Motor Course Design Calculation, Working Principle & Design Example Online advance Course

HOW TO CRACK RRB SSE AND JE , AWESOME TIPS AND TRICKS.

List of All online Courses