Rony Parvej_s EEE Job Solution Part 1 (PGCB 2014)

Rony Parvejs EEE Job Solution PGCB- , BUET

Recruitment Test Question of Power Grid Company of Bangladesh (PGCB) Compiled & Solved by: Rony Parvej (IUT, EEE07)

Post: Assistant Engineer (Electrical)

Time: 90 minutes Full Marks: 100

Exam Date: 31.01.2014 Venue: BUET

[ - MCQ ( ), MC Q ( ), ( ) ]

MCQ ( Non-Departmental) 60 x 0.5 =30 1. Which Country has longest land border with India?

(a) Pakistan (b) China (c) Bangladesh (d) Nepal

[Bangladesh: 4,053 km China : 3,380 km Pakistan : 2,912 km Nepal: 1,690 km ]

2. ELLORA a historical place with great archaeological importance is located in - (a) China (b) Egypt (c) India (d) Peru

[ , ]

3. Musa Ibrahim ascended Mount Everest on-

(a) 2009 (b) 2010 (c) 2011 (d) 2012

()

,

4. How many One-Day-Internationals did Sachin Tendulker play in his glorious cricket carrier?

(a) 200 (b) 463 (c)785 (d) 1132

, . *

, . *

5. Which type of fire extinguisher is used for petroleum fire?

(a) Powder type (b) Liquid type (c) Soda Acid type (d) Foam type

Choosing Fire Extinguishers

Class A: SOLIDS such as paper, wood, plastic etc

Class B: FLAMMABLE LIQUIDS such as paraffin, petrol, oil etc


Class C: FLAMMABLE GASES such as propane, butane, methane etc

Class D: METALS such as aluminium, magnesium, titanium etc

Class E: Fires involving ELECTRICAL APPARATUS

Class F: Cooking OIL & FAT etc

[A for Ash, B for Barrel, C for cylinder, D for Dynamite, E for Electrical apparatus, F for fat and oil}

Water Fire Extinguishers: The cheapest and most widely used fire extinguishers. Used for Class A fires. Not suitable for Class B (Liquid) fires, or

where electricity is involved.

Foam Fire Extinguishers: More expensive than water, but more versatile. Used for Classes A & B fires. Foam spray extinguishers are not

recommended for fires involving electricity, but are safer than water if inadvertently sprayed onto live electrical apparatus.

Dry Powder Fire Extinguishers: Often termed the multi-purpose extinguisher, as it can be used on classes A, B & C fires. Best for running liquid fires (Class B). Will efficiently extinguish Class C gas fires, BUT BEWARE, IT CAN BE DANGEROUS TO EXTINGUISH A

GAS FIRE WITHOUT FIRST ISOLATING THE GAS SUPPLY. Special powders are available for class D metal fires.

Warning: when used indoors, powder can obscure vision or damage goods and machinery. It is also very messy.

CO2 Fire Extinguishers: Carbon Dioxide is ideal for fires involving electrical apparatus, and will also extinguish class B

liquid fires, but has NO POST FIRE SECURITY and the fire could re-ignite.

Wet chemical: Specialist extinguisher for class F fires.

For Metal Fires: A specialist fire extinguisher for use on Class D fires - metal fires such as sodium, lithium, manganese

and aluminium when in the form of swarf or turnings.

6. Which year of the following is not a Leap Year? (a) 2000 (b) 1900 (c) 2012 (d) None of these

[ : . , , : ]

7. Bengali Calendar year was introduced by the ruler -

(a) Akbar (b) Asoke (c) Sirajuddoula (d) Shahjahan

[ / , , ]

8. Victoria Falls is located in - (a) Canada (b) South Africa (c) United States (d) Zambia

[Victoria Falls is a waterfall in southern Africa on the Zambezi River at the border of Zambia and Zimbabwe.]


9. Winston Churchill was premier of -

(a) United States (b) Canada (c) Australia (d) United Kingdom

[ ]

10. The artist of the painting Last Supper was - (a) Michael Angelo (b) Leonardo-da-Vinci (c) Pablo Picasso (d) Van Gogg

11. Who is the designer of Oporajeyo Bangla at DU campus? (a) Sayed Abdullah Khaled (b) Sayed Moinul Hossain (c)Hamidur Rahman (d) Louis Kahn

12. eV is unit of (a) Energy (b) Power (c) Charge (d)

13. A tuning fork of 480 Hz is in unison with pipe closed at one end vibrating in its first overtone.

Then fundamental frequency of the pipe is-

(a) 150 Hz (b) 160 Hz (c) 480 Hz (d) 190 Hz

[ unison first overtone vibratee ]

14. A weight of 5 Kg is required to produce the fundamental frequency of a sonometer wire. What

weight is required to produce its octave?

(a) 30 Kg wt (b) 10 Kg wt (c) 20 Kg wt (d) 40 Kg wt

[ n1 n2 n2 n1 (octave) , n1

n2=

2

1 . ,

, n = 1

2 l

T

m . n = , l = , T = , m= ,

, = m2

m1. m2 = m1.(

n1

n2 )2 . m2 = 5.(

2

1 )2 ] = 20 Kg ]

15. The operation carried out by Pakistan army on 25th

March 1971 was code named-

(a) Operation Search Light (b) Operation Red Hunt

(c) Operation Clean Heart (d) Operation Jackpot

16. Study of life in outer space is known as (a) Endobiology (b) Neobiology (c) Extrobiology (d) Exobiology

17. Brass gets discoloured in air because of the presence of which of the following gases in air?

(a) Hydrogen sulphide (b) Oxygen (c) Carbon dioxide (d) Nitrogen

The Cu present in brass reacts with the sulphide ion of H2S forming CuS (cupric sulphide) which is black colored. Thus

when brass is exposed to air it gets discolored.

18. Which of the following metals forms an amalgam with other metals -

(a) Tin (b) Zinc (c) Lead (d) Mercury

Tips: Amalgam is a substance formed by the reaction of mercury with another metal. Almost all metals can form amalgams

with mercury, notable exceptions being iron and platinum.

19. Which district of Bangladesh has borders with both India and Myanmar ?

(a) Rangamati (b) Khagrachori (c) Coxs bazaar (d) Bandarban

20. Olympic 2016 will be held in-

(a) Beijing (b) London (c) Brazil (d)


21. The fastest memory that is used in the computer system is-

(a) Hard disk (b) Random Access Memory (c) Cache Memory (d) Tape Memory

22. Which of the following is not an operating system?

(a) Java (b) Linux (c) Ubuntu (d) Android

[Java is a programming language]

23. Which of the following is not valid file name extension?

(a) .xsl (b) .doc (c) .docx (d) .xls

24. The clock speed of the processors that are used in PC in present time is in the range of -

(a) Megahertz (b) Gigahertz (c) Gigabyte (d) Megabyte

25. What is LAN?

(a) Local Area Network (b) (c) (d)

26. The binary value of 14 is -

(a) 1100 (b) 1110 (c) 1011 (d) 1111

27. Which of the following is a database management system?

(a) Microsoft Windows (b) Microsoft Excel (c) Microsoft Access (d) Microsoft Word

28. Who discovered circulation of blood in human body?

(a) Edward Jenner (b) William Harvey (c) Joseph Lister (d)

29. By Keeping moment of inertia of a body constant, if we double the time period, then angular

momentum of body -

(a) Remains constant (b) Becomes half (c) Doubles (d) Quadruples

[ , L = I = I.2 /T. (moment of inertia) I (angular momentum ) L, T angular momentum ]

30. if x, y, z are quantites of same kind and x:y = 3:4 and y:z = 8: 7, what will be x:y:z ?

(a) 3:4:7 (b) 3:8:7 (c) 3:12:7 (d) 6:8:7

31. Given the first seven number of a series: 1, 3, 6, 10, 15, 21 what will be the 8th and 9th numbers?

(a) 36 and 45 (b) 35 and 44 (c) 36 and 44 (d) 35 and 46

[1+2=3, 3+3 =6, 6+4=10, 10+5=15, 15+6=21, 21+7=28, 28+8=36 and 36+9 = 45 ]

32. Given two equations: 3x-y=4 and x+5y=28. What are the values of x and y respectively?

(a) 3 and 6 (b) 4 and 6 (c) 4 and 5 (d) 3 and 5

33. A person started driving his car with a velocity of 80 Km/hour from Dhaka to Chittagong. After a

half an hour, another person started from the same location with a car of velocity 120 km/hour. At

what time after starting the second car, the second car will cross the first one.

(a) 1 hour and 30 minutes (b) 2 hours (c) 1 hour (d) None of these

[40+80t = 120t , so t=1 ]


34. If a person invests 5000 taka with a monthly profit of 15% and 10000 with a monthly profit of

10%, what will be the average profit?

(a) 12.55% (b) 11.55% (c) 11.66% (d) 12.66%

[profit = .15*500 + .1*10000 = 1750 taka; 1750/15000 = .1166 =11.66%]

35. A 1200 Kilogram car travelling at 10 meter per second hits a tree and is brought to rest in 0.1

second. What is the magnitude of average force acting on the car to bring it to rest?

(a) 1.2 x 102 N (b) 1.2 x 103 N (c) 1.2 x 104 N (d) 1.2 x 105 N

36. Bell Metal is an alloy of (a) Nickel and copper (b) zinc and copper (c) brass and nickel (d) tin and copper

37. Paper is made ---- wood.

(a) of (b) by (c) from (d) on

[ make of The table is made of wood. make from Paper is made from wood. Sweets are made from milk.]

38. The synonym of Resentment is- (a) fear (b) panic (c) Indignation (d) anger

[ Resentment = , , ]

39. A Bull market means that share prices are- (a) (b) (c) rising (d) decling

[ Definition of 'Bull Market: A financial market of a group of securities in which prices are rising or are expected to rise.

The term "bull market" is most often used to refer to the stock market, but can be applied to anything that is traded, such as

bonds, currencies and commodities.]

40. As the sun -----, I decided to go home.

(a) has shine (b) shine (c) shines (d) was shining

[ Principal clause past tense subordinate clause past tense ]

41. Which one of the following sentence is correct?

(a) Why have you done this? (b) Why you had done this?

(c) Why you have done this? (d) Why did you done this?

[ (a) Why have you done this? ]

42. We will reach there ----- five minutes.

(a) within (b) by (c) (d)

43. run . in a few months (a) out (b) away (c) (d)

44. The historic battle field of waterloo is located in present (a) Germany (b) Belgium (c) France (d) United Kingdom


' ( ) ,

45. The name of Malaysian currency is-

(a) Dinar (b) Bath (c) Ringgit (d) Rubble

46. Which of the following problem is not created by noise pollution?

(a) Diarrhoea (b) Hypertension (c) Deafness (d) Irritation

47. Who among the following is associated with the invention of computer?

(a) Edison (b) Babbage (c) Mac Millen (d)

48. Water rises up to a height h1 in a capillary tube of radius r. The mass of the water lifted in the

capillary tube is M. If the radius of the capillary tube is doubled the mass of the water that will rise

in the capillary tube will be-

(a) M (b) 3M (c) 2M (d) 4M

49. I opened the door as soon as I ----- the bell.

(a) have heard (b) heard (c) am heard (d) was hearing

[(b) heard ]

50. Through thick and thin means- (a) to make thick and thin (b) to clear understanding

(c) Under all conditions (d) of great density

51. Hurry up! We have to go ---- five minutes.

(a) by (b) within (c) in (d) on

[ by ]

52. The word electorate means (a) election office (b) a body of voters (c) many elections (d) candidates

53. Nobody knocked him down. It was an -

(a) accident (b) incident (c) adversity (d) occurrence

54. If we want concrete proof, we are looking for (a) building material (b) clear evidence (c) something to cover a path (d) a cement mixer


55. They have ---- their support for our case.

(a) provided (b) pledged (c) deferred (d) disavowed

[ pledged provided ]

56. The antonym of Recalcitrant is (a) compliant (b) passive (c) adversity (d) careful

[Recalcitrant - , ]

57. Length of a pond is 10 meter and width is 6 meter. There is a road around the pond and the width

of the road is 2 meter. What is the area of the road?

(a) 100 sq. meter (b) 64 sq. meter (c) 70 sq. meter (d) 80 sq. meter

[(2+10+2)*(2+6+2) 10*6 = 140 -60 =80]

58. Internet Protocol version 6 (IPV6) is the latest revision of the Internet Protocol (IP) that uses:

(a) 256 bit address (b) 128 bit address (c) 132 bit address (d) 64 bit address

[IPv6 uses a 128-bit address and IPv4 uses 32-bit addresses.]

59. Two stars A and B radiate maximum energy at 3600A and 3600A respectively. Then the ratio of

absolute temperatures of A and B is (a) 256: 81 (b) 81: 256 (c) 3: 4 (d) 4: 3

[ 3600A 4800A mt = , t1/t2 = 2/1 = 4800/3600 = 4:3 ]

MCQ ( Departmental) 25 x 1 =25

1. In UNIT transformer is used as - (a) Energy meter (b) (c) (d)

2. Current in parallel resonant circuit is (a) maximum (b) minimum (c) (d) none of these

3. At noise which diode is better between Si and Ge-

(a) Si (b) Ge (c) (d)

4. Which one is used in solar photovoltaic (a) PN junction (b) Electromechanical device (c) Quantum device (d)

5. At zero degree celcius temperature Intrinsic Si material behaves like (a) metal (b) insulator (c) (d)None of these

[Because no free electrons are available for current conduction at 0C temperature]

6. In Dc machine, field is connected with-

(a) rotor (b) armature (c) (d)

7. In open circuit test of transformer power supply is given in


(a) low voltage side (b) high voltage side (c) (d)

8. By field control we can only obtain speed (a) higher than normal speed (b) lower than normal speed. (c) (d)

9. If Shunt resistance is increased in motor, then speed will

(a) increase (b) decrease (c) (d)

10. In Yg phase difference between ang Y is (a) 0 (b) 30 (c) 60 (d) 90

11. Synchronous condenser is used in (a) Under excited DC (b) Under excited AC (c) Overexcited AC (d)

12. If load is increased then terminal voltage of a battery will

(a) remain same (b) increase (c) decrease (d)

13. The main superiority of digital communication over analog communication is

(a) electronic circuit can be used (b) A/D and D/A converter can be used (c) (d)

14. A PCM system multiplexes 10 band limited voice channel (300-3400 Hz) and uses a 256 level

quantizer, considering the standard sampling rate for telephone system the bandwidth of binary

encoded signal is-

(a) 640 Kb/s (b) 80 Kb/s (c) 248 Kb/s (d) 496 Kb/s

[ 256 = 28 =2

n . so, no. of bits n =8.

Standard sampling frequency, fs = 8KHz

So, Bandwidth for every channel, Rb = nfs = 8*8 =64 KHz

So, Bandwidth for 10 channels = 64*10 = 640 KHz ]

15. Si has (a) direct bandgap (b) indirect bandgap (c) semi-direct bandgap (d)


Written ( Departmental) 13 x 3 + 6 =45

1. Find I1 and I2 of the following circuit.

Answer:

If the diodes are Si diode,

So, I1 = 0 A [diode will not conduct as voltage difference between +ve and ve terminal is less than 0.7 V]

I2 = (5 3 - 0.7) / 5000 = 0.26 mA

If the diodes are Ge diode, I1 = 0 A and I2 = (5 3 - 0.3) / 5000 = 0.34 mA

If diode drops are neglected, I1 = (5- 5)/5000 = 0 A and I2 = (5 3) / 5000 = 0. 4 mA

2. Convert the star network to delta:

Answer: Let, Z1 = 10 , Z2 = j10 and Z3 = -j120

ZA = (Z1* Z2 + Z2 * Z3 + Z3 * Z1 ) / Z1

= ( j100 + 1200 j1200 )/10 = (1200 j1100)/10 = 120 j110

ZB = (Z1* Z2 + Z2 * Z3 + Z3 * Z1 ) / Z2

= (1200 j1100) / j10 = - j120 -110

= -110 j120

ZC = (Z1* Z2 + Z2 * Z3 + Z3 * Z1 ) / Z3

= (1200 j1100)/ -j120

= j10 + 9.17 = 9.17 +j10

3. Show the direction of the current in primary and polarity of the load initially:

Answer:

Tips:


Based on the dot convention, a current entering the dotted terminal of one coil, will induce positive voltage at the dotted

terminal of the second coil. Alternatively, if the current leaves the dotted terminal of the coil, it will induce negative voltage

at the dotted terminal of the second coil.

Referring to the circuit diagrams below:

The circuit polarity signs '+' and '-' indicate example applied and resultant, relative voltage polarities.

The instantaneous polarities of the voltages across each inductor with respect to the dotted terminals are the same.

The circuit arrows indicate example applied and resultant relative current directions.

The instantaneous directions of the current entering the primary inductor at its dotted end and the current leaving of the secondary inductor at its dotted end are the same.

Subtractive polarity transformer designs are shown in the upper circuit diagrams. Additive polarity transformer designs are shown in the lower circuit diagrams.

4. A motor has copper loss of 300 W and 4.5% slip. How much electrical power is converted to

mechanical power?

Answer: Here, Copper loss, Pcr = 300 W. Slip, s = 4.5% = 0.045. Electrical Power converted to mechanical, Pm = ?

We Know, Pcr / Pm = s /1-s.

Pm = Pcr*(1-s) /s = 300 * (1- 0.045) / 0.045 = 6366.67 W Ans.

Tips: P2 : Pcr : Pm = 1 : s : 1-s.

Where, P2 = Electrical power input in rotor; Pm = Electrical Power converted to mechanical

Pcr = I2R = Copper loss

[Ronys Special tips: - , % s. Pm , : P2 : Pcr : Pm = 1 : s : 1-s. .% ( - .)% = .% .% = % = /. .% = .*/. = . ! ! ]


5. Draw the structure of an optical fibre and write the name of different components of optical fiber

communication.

Answer: Components of optical fiber communication:

1. Information source

2. Electrical Transmitter

3. Optical source

4. Optical fiber cable

5. Optical detector / Photodetector

6. Electrical receiver

7. Destination.

Figure: structure of an optical fiber

6. In a resonant RLC circuit R=10 , XL=200 , f = 50 Hz. If 100 V voltage is applied what will be the voltage drop across capacitor?

Answer: For resonance, Z = R = 10 So, I = V/Z = 100/ 10 = 10 A.

So, VC = I XC = 10*200 =2000 V Ans.

[Tips: Series resonant circuit across ! ]

7. What are the no load and full load losses of transformer?

Answer: No Load Losses:

Iron loss: Hysteresis and eddy current loss

Very small amount of copper loss also occurs in primary

Full Load losses:

At full load, Copper loss is largest and a very small amount of eddy current loss is there.

8. Draw the diagram of a Dc motor starter.

Answer:


9. Find the value of R in the following circuit:

Answer:

R =( 6 0.7) / 1.1 = 4.82 K

10. For maximum bandwidth B draw the frequency spectrum of DSB-SC and SSB.

Answer:

Figure: frequency spectrum of DSB-SC

Figure: frequency spectrum of SSB


11. A 3-phase delta connected R-L load has line voltage of 400V. In each phase R=10 and XL=j10.

Find line current and total power of the circuit.

Answer:

Here, VL = VPh = 400 V; Zph = 10 + j10 = 14.14 45 ; IL =? P=? Iph = VPh / ZPh = 400 / 14.14 45 = 28.29 45

Pactive = 3* VPh* Iph*Cos = 24, 004.72 KW

12. Convert 0.25 p.u. reactance of 500MVA, 18 KV to new p.u. reactance having new bases of 100

MVA and 18 KV.

Answer:

P.u.new = P.u.old * (MVA new / MVAold ) * (KV new / KVold)2

= 0.25 (100/500)*(18/18)2

= 0.05

p.u. Ans.

13. Maximum efficiency of a transformer is 98%. It runs at 50% efficiency for 14 hours and at no

load for remaining 10 hours. Find its all day efficiency. ( )


14. LLL-G fault related problem. (6 marks)

A 100kva alternator is connected with 10kv bus bar.a 3 phase to ground fault occurs at the bus-

bar.the bus bar impedance is 1+2j pu.find fault current.

Current = 1

1+2pu

Base Current =100

3 (10)

https://facebook.com/ronyiut - [email protected]

EEE JOB PREPARATION facebook Group: https://facebook.com/groups/468599736538711?refid=27

( , )

1 pu

source

1+2j

pu

Rony Parvej_s EEE Job Solution Part 1 (PGCB 2014)

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