Sunday, July 31, 2016

Questions Based On Transmission



Q1:- Feature of long transmission line is 
  1. length is 150 km and line voltage is 33 kv 
  2. length is 150 km and line voltage is 66 kv 
  3. length is 150 km  and line voltage is above 100 kv 
  4. none of the above
ANSWER:- 3

Q2:- Types of insulator 
  1. pin type insulator 
  2. suspension type insulator
  3. strain type insulator
  4. shackel type insulator
  5. edge type insulator 
  6. all
ANSWER:-6

Q3;- In pin type insulator conductor passes through from 
  1. goove
  2. pin
  3. both 
  4. none 
ANSWER:- 1

Q4:- Pin type insulator can be used 
  1. upto 33 kv 
  2. upto 66 kv 
  3. upto 11 kv 
  4. none
ANSWER:- 1

Q5:- Safety factor of pin type insulator is approx
  1. 9
  2. 10
  3. 11
  4. 12
ANSWER:- 2

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Saturday, July 30, 2016

Questions Based On DC Derives

Q1:- Type of D.C. drives is 

  1. regenerative 
  2. non regenerative 
  3. single phase D.C. drives
  4. all
ANSWER:- 4

 Q2:- Which of the following is true for regenerative D.C. drive 

  1. by it speed of motor can be control in both direction
  2. by it can be control motor's speed and torque direction 
  3. both 1 and 2 
  4. none of the above 
ANSWER:-3

 Q3:- Which of the following is true for non regenerative d.c. drive 

  1. by it speed of motor and direction of the rotation can control in only one direction
  2. it is cheaper than regenerative drive 
  3. both 1 and 2 
  4. none of the above
ANSWER:-3

 Q4:- To increases the motor speed from base speed used 

  1. voltage regulator 
  2. regulator 
  3. field regulator 
  4. none of the above 
ANSWER:-3

 Q5:- To decrease the motor's speed from base speed used 

  1. voltage regulator
  2. field regulator
  3. thyristor circuit
  4. none 
ANSWER:-2
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Friday, July 29, 2016

Electrical Transmission Questions.

Q1;- Safety factor of steel tower is 
  1. 1
  2. 2
  3. 3
  4. 4
ANSWER:- 2

Q2:- Life of the steel tower is 
  1. 80 yr
  2. 70 yr
  3. 60 yr
  4. 100 yr
ANSWER:- 1

Q3:- Types of overhead transmission line is 
  1. short transmission line ( low voltage line)
  2. medium transmission line ( medium voltage line )
  3. long transmission line (high voltage line)
  4. all
ANSWER:- 4

Q4:- Feature of short transmission line is 

  1. length is less than 50 km and line voltage is less than 20 kv
  2. length is less than 100 km and line voltage is 33 kv
  3. length is less than 100 km and line voltage is 66 kv 
  4. none of the above 
ANSWER:- 1

Q5:- Feature of medium transmission line is
  1. length is 50 - 150 km and line voltage is 20 kv - 100 kv 
  2. length is 100 - 200 km and line voltage is 400 kv
  3. length is 50 150 km and line voltage is 66 kv 
  4. none 
ANSWER:- 1


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Thursday, July 28, 2016

Electrical Transmission Based Questions

Q1:- Height of R.C.C. pole is 

  1. 100 yr 
  2. 200 yr 
  3. 400 yr 
  4. 50 yr 
ANSWER:-1

 Q2:- Transmission line voltage is used in steel tower is 

  1. 11 kv 
  2. 33 kv
  3. 132 kv or above
  4. none of the above
ANSWER:-3

 Q3:- shape of steel tower is 

  1. angle type 
  2. I type 
  3. both 1 and 2
  4. none 
ANSWER:-3

 Q4:- Maximum votage line of R.C.C. pole is 

  1. 230 v to 33 kv
  2. 400 v to 33 kv 
  3. 110 v to 22 kv 
  4. none
ANSWER:-1

 Q5:- Span of steel tower is 

  1. 100 to 200 meter
  2. 150 to 200 meter
  3. 300 to 400 meter
  4. none 
ANSWER:-2
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Wednesday, July 27, 2016

SSC Jr Engg. Basic Questions

Q1:- Types of steel pole used 

  1. rail pole type
  2. tubular steel pole type
  3. rolled steel joints type 
  4. all of the above 
ANSWER:- 4

 Q2:- Transmission line on steel pole can be used 

  1. upto 11 kv
  2. 11 to 33 kv 
  3. 33 to 66 kv 
  4. all 
ANSWER:- 2

 Q3:- Span of the steel pole should be 

  1. 150 meter
  2. 200 meter
  3. 400 meter
  4. none of the above
ANSWER:- 1

 Q4:- To increase the life of steel pole we should used 

  1. galvonised iron or paint 
  2. steel coating
  3. CRGO material 
  4. none of the above
ANSWER:- 1

 Q5:- Span of the R.C.C. pole is 

  1. 100 - 200 meter
  2. 60 - 200 meter
  3. 100 - 50 meter
  4. none of the above 
ANSWER:- 2
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Tuesday, July 26, 2016

Basic Questions

Q1:- Wooden pole is used for 

  1. 11 kv - 22 kv
  2. 33 kv - 66 kv 
  3. both 
  4. none of the above 
ANSWER:- 1

 Q2:- Life of wooden pole is 

  1. 10 to 20 yr
  2. 20 to 25 yr
  3. 5 to 10 yr 
  4. none of the above 
ANSWER:-2

 Q3:- Wooden pole are in shape of 

  1. A type 
  2. H type 
  3. I type
  4. both 1 and 2 
ANSWER:-4

 Q4:- To prevention ground part of the wooden pole we should use

  1. karosin oil
  2. musterd oil 
  3. coconut oil
  4. pam oil
ANSWER:-1

 Q5:- The height of wooden pole is 

  1. 10 to 15 meter
  2. 5 to 10 meter
  3. 35 to 40 meter
  4. none of the above
ANSWER:-1
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Monday, July 25, 2016

BSNL TTA Practice Questions

Q1:- When both synchro transmitter and receiver rotors are displace from zero by the same angle they are in 

  1. correspondence 
  2. phase
  3. error
  4. unbalanced field synchronism
ANSWER:- 4

 Q2:- capacitor start capacitor run motor is generally coupled with the air conditioner compressor because it 

  1. takes low starting as well as running current
  2. is cheaper
  3. is quit in operation 
  4. does not require any maintenance 
ANSWER:-1

 Q3:- A capacitor start capacitor run motor has two capaciotrs. when the motor is started 

  1. only one of the capacitors is in circuit 
  2. both the capacitors are circuit and are connected in parallel
  3. both the capacitors are in circuit and are connected in series
  4. both are in series 
ANSWER:-2

 Q4:- By pushing and pulling the rotor shaft a motor can be checked for 

  1. end play 
  2. side play
  3. firm mounting
  4. free shaft movement 
ANSWER:-1

Q5:- Armature short circuits can be detected and identified by which of the following tests?
  1. bar to bar 
  2. voltage drop
  3. growler 
  4. all of the above
ANSWER:-4
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Sunday, July 24, 2016

BSNL TTA Practice Question

Q1:- In a single phase induction motor 
  1. both the main and auxiliary windings are placed on the stator 
  2. both the main and auxiliary windings are paced on the rotor
  3. the main winding is on stator and the auxiliary winding is on rotor
  4. none of the above
ANSWER:- 1

Q2:- The rotor windings of a synchro control transformer are 
  1. never connected to the A.C. supply 
  2. connected to the CT taps 
  3. for 3-phase power input only
  4. connected to the A.C. supply 
ANSWER:-1

Q3:- The direction of rotation in a conventional shaded -pole motor can be reversed by 
  1. reversing the line connections 
  2. using a capacitor 
  3. reversing the rotor 
  4. reversing the stator poles 180 degree
ANSWER:-4

Q4:- The effective voltage induced in any synchro transmitter coi depends on the angular position of the 
  1. the differential field flux 
  2. the A.C. magnetic field of the rotor
  3. a D.C. source 
  4. compensation windings
ANSWER:-2

Q5:- If the centrifugal switch of a capacitor start motor fail to open
  1.   the motor will come to stop
  2. the auxiliary winding will be damaged the capacitor will be destroyed.
  3. the capacitor will be destroyed 
  4. none of the above 
ANSWER:-3
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Saturday, July 23, 2016

BSNL TTA Practice Questions

Q1:- The cheapest motor in the fractional horse power motors is 

  1. split phase motor
  2. capacitor start motor
  3. shaded pole motor
  4. none of the above
ANSWER:- 3

 Q2:- The motor generally used in house hold food mixer is 

  1. shaded pole motor
  2. universal motor
  3. capacitor start motor
  4. none of the above
ANSWER:- 2
Q3:- The direction of rotation of 1-phase capacitor motor (fan) can be reversed in interchanging connection of 

  1. main winding and starting winding 
  2. starting winding only 
  3. main winding only 
  4. any one of the starting or main winding 
ANSWER:- 4

 Q4:- The D.O.R. of shaded pole type motor can be reversed by 

  1. interchanging the supply terminals 
  2. interchanging the main winding terminals 
  3. reversing the position of the rotor
  4. none of the above
ANSWER:- 3

 Q5:- When a single phase motor picks up predetermined speed its starting winding is disconnected but still it continue to run on

  1. compensating winding 
  2. main winding 
  3. starting winding 
  4. rotor winding
ANSWER:- 2
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Friday, July 22, 2016

BSNL TTA Question

Q1:- A synchro- transmitter sends an electrical signal to the 

  1. synchro receiver 
  2. motor field
  3. motor starter 
  4. synchro generator 
ANSWER:- 1
Q2:- The direction of rotation of a hysteresis motor is determined by the 

  1. hysteresis loss 
  2. magnetic retentivity of the rotor
  3. position of the shaded pole with respect to the main pole 
  4. magentic permeability of the stator 
ANSWER:- 3
Q3:- Running overload protection in a manual starting switch is provided by a 
  1. dual element fuse
  2. toggle switch 
  3. thermal activated device 
  4. snap action mechanism
ANSWER:- 3

Q4:- A singe phase motor is 
  1. self starting 
  2. not self starting 
  3. self starting with the help of auxiliary winding
  4. self starting with the help of capacitor in series.
ANSWER:- 3

Q5:- Motor and controller frames must be grounded to 
  1. prevent a potential above ground 
  2. have a common return path 
  3. eliminate a grounding conductor 
  4. isolate the motor from overcurrents 
ANSWER:- 1
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Thursday, July 21, 2016

Junior Engg.

Q1:- The permissible voltage drop from supply terminal to any point on the wiring system should not exceed?

  1. 1% + 1 volt
  2. 4% + 1 volt
  3. 2% + 1 volt 
  4. 3% + 1 volt
ANSWER:- 3

 Q2:- If an RLC series circuit the frequency is below the reasonant frequency then 

  1. none of the options
  2. Xc < XL
  3. Xc > XL
  4. Xc = XL
ANSWER:- 4

 Q3:- If the power factor is high then the consumer maximum KVA demand

  1. remains constant
  2. deceases 
  3. increases 
  4. becomes zero 
ANSWER:- 2

 Q4:- If the co- efficient of coupling between two coils is increased mutual inductance between the coils

  1. it gives regulation value higher than its actual found by direct loading
  2. armature reaction is wholly magnetising 
  3. it is simplest to perform and compute
  4. it gives regulation value lower than its actual found by direct loading 
ANSWER:- 1

 Q5:- Electrical resistivity of ROW is 

  1. low for copper and high for alloy 
  2. high for copper as well as for alloy
  3. low for copper as well as for alloy 
  4. high for copper and low for alloy
ANSWER:- 1

Read more »
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Wednesday, July 20, 2016

BSNL TTA Questions


Q1:- The per phase D.C. armature resistance of an alternator is 0.5 ohm. The effective a.c. armature resistance resistance  would be about ?

  1. 1 ohm
  2. 0.25 ohm 
  3. 0.5 ohm
  4. 0.75 ohm 
ANSWER:- 4
Q2:- When a source is delivering maximum power to the load the efficiency will be 


  1. below 50%
  2. 50%
  3. maximum
  4. above 50 %
ANSWER:- 2

 Q3:- When a series RL circuit is connected to a voltage source V at t=0, the current passing through the inductor L at t=0+ is 


  1. V/L
  2. V/R
  3. infinite
  4. zero
ANSWER:- 4

 Q4:- A node in a circuit is define as a 


  1. closed path 
  2. junction of two or one more 
  3. group of interconnected 
  4. open terminal of an
ANSWER:- 2

 Q5:- Leakage flux in a transformer occurs because 


  1. transformer is not an efficient device 
  2. iron core has high permeability 
  3. applied voltage is sinusoidal 
  4. air is not a good magnetic insulator 
ANSWER:- 2

Read more »
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Tuesday, July 19, 2016

Junior Engg. Questions

Q1:- The electric drive posses the following drawback?

  1. requires a continuous power supply
  2. not available with various rating  
  3. not adoptable to various environments
  4. requires hazardous fuel requirement 
ANSWER:- 1

 Q2:- Three wattmeter method of power measurement can be used to measure power in 

  1. none of the options 
  2. balanced circuits
  3. both balanced and unbalanced circuit 
  4. unbalanced circuits
ANSWER:- 2
Q3:- The unit of luminous flux is ?

  1. lumen 
  2. steradian 
  3. lux 
  4. candela 
ANSWER:- 1

 Q4:- One sine wave has a period of 2 ms another has a period of 5 ms and other has a period  of 10 ms . which sine wave is changing at a faster rate ?

  1. sine wave with period of 10 ms
  2. sine wave with period 5 ms 
  3. sine wave with period 2 ms 
  4. all are at the same rate 
ANSWER:- 3

 Q5:- A  batton wiring the cables are carried on seasoned teak wood perfectly straight and well varnished teak wood batton of thickness not less than ?

  1. 4 cm 
  2. 1 cm
  3. 2 cm
  4. 3cm
ANSWER:- 2

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Monday, July 18, 2016

Junior Engg. Questions

Q1:-In a parallel RLC circuit if the lower cut off frequency is 2400 Hz and the upper cut off frequency is 2800 Hz what is the band width?

  1. 400 Hz
  2. 5200 Hz
  3. 2400 Hz
  4. 2800 Hz 
ANSWER:- 1


Q2:-How much energy is stored by a 100 mH inductance when a current at the rate of 2 A/sec , then emf induced in the other coil is ?
  1. 0.005 J
  2. 5.0 J
  3. 0.05 J
  4. 0.5 J
ANSWER:- 3

Q3:- If a dynamometer type wattmeter is connected in an ac circuit the power indicated by the wattmeter will be 
  1. peak power
  2. average power
  3. instantaneous power 
  4. volt ampere product 
  5. ANSWER:- 2

Q4:- If the number of turns of a coil is increased, its indctance
  1. remains the same
  2. is decreased
  3. non of these
  4. is increased
ANSWER:- 4

Q5:- Base load of a power station stands for?
  1. 2-4 hours/day
  2. 4-8 hours/day
  3. 12-24 hours/day
  4. 8-12 hours/day
ANSWER:-3
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Sunday, July 17, 2016

Electrical Questions

Q1:- which of the following motor is non- self starting ?

  1. squirrel cage induction motor
  2. synchronous motor
  3. dc series motor
  4. slip ring induction motor
ANSWER:-2
Q2:- If span length is double with no change in other factors,the sag of the line will become ?

  1. 2 times 
  2. 8 times
  3. 0.5 times
  4. 4 times
ANSWER:-4

 Q3:- If 750 micro Amper is flowing through 11 K ohm of resistance , what is the voltage drop across the resistor?

  1. 8.25 V
  2. 146 V
  3. 82.5 V
  4. 14.6 V
ANSWER:-1

 Q4:- The Ta Vs Ia graph of a dc series motor is a 

  1. parabola from no load to over load
  2. straight line throughout
  3. parabola throughout
  4. parabola up to full load and a straight line at over load 
ANSWER:-4

 Q5:- A resistor is connected across a 50 V source. The current in the resistor if the colour code is red ,orange silver is 

  1. 214 mA
  2. 2.2 mA
  3. 2 mA 
  4. 21.4 mA
ANSWER:-2

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Saturday, July 16, 2016

Junior Engg. Paper Set

Q1:- When the current through the coil of an electromagnet reverses the 

  1. direction of the magnetic field remains unchanged 
  2. direction of  the magnetic field reverses
  3. magnetic field expands
  4. magnetic field collapses
ANSWER:- 2

 Q2:- Thevenin's theorem can not be applied to
  1. passive circuit
  2. active circuit
  3. linear circuit
  4. nonlinear circuit
ANSWER:- 4

 Q3:- A 10 pole 25 hz alternator is directly couple to and is driven by 60 hz synchronous motor then the number of poles in a synchronous motor are

  1. 24 poles
  2. 12 poles
  3. 48 poles
  4. none
ANSWER:- 1

 Q4:- The motor used on small lathes is usually

  1. universal motor
  2. single phase capacitor run
  3. dc shunt motor
  4. 3-phase synchonous
ANSWER:- 2

 Q5:-In dc operation of flourescent tube the life of the tube 

  1. may increase or decrease
  2. remain same
  3. increases by about 80 % as that with ac operation
  4. decreases by about 80 % as that with ac operation
ANSWER:- 4

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Friday, July 8, 2016

Junior Engg. Paper Sets

Q1:- The primary and secondary windings of a transformer are wound on the top of earth other in order to reduce...?

  1. winding resistance
  2. copper losses
  3. leakage reactance 
  4. iron losses 
ANSWER:-3
Q2:- A salient pole synchronous motor is operating at 1/4 th full load . if its field current is suddenly switched off it would

  1. run at cub synchronous speed
  2. run at super synchronous speed
  3. continue to run at synchronous speed
  4. stop running
ANSWER:-3
Q3:- What is the maximum number of point of light fan and socket - outlets that can be connected in one sub circuit

  1. 6
  2. 10
  3. 4
  4. 12
ANSWER:-2

 Q4:- The acceptable value of ground resistance for domestic application is ?

  1. 1 ohm
  2. 2 ohm
  3. 1.5 ohm
  4. 0.5 ohm
ANSWER:-1

 Q5:- Silicon has a preference in IC technology because

  1. it is a covalent semiconductor
  2. it is an indirect semiconductor
  3. of the availabity of nature oxide SiO 
  4. it is an elemental semiconductor
ANSWER:-3

 Q6:- The purpose of starting winding in a singe phase induction motor is to ?

  1. reduce losses
  2. increase losses
  3. produce rotating flux in conjunction with main winding
  4. limit temperature rise of the machine
ANSWER:-3

 Q7:- The no load primary current I is about of full load primary current of a transformer
  1. above 40%
  2. 3-5%
  3. 15-30%
  4. 30-40%
ANSWER:-2

Q8:- The no load i/p power to a transformer is practically equal to loss in the transformer
  1. windage 
  2. iron
  3. eddy current
  4. copper
ANSWER:-2

Q9:- Each of the following statements regarding a shaded poe moto is true except:
  1. it has very poor efficiency 
  2. its direction of rotation is from unshaded to shaded portion of poles 
  3. it has high starting torque 
  4. it has very poor power factor
ANSWER:-3

Q10:- An arc bow is a welding defect that is countered with the help of carrying
  1. the resistance welding 
  2. the thermit welding
  3. the arc welding using AC supply
  4. the arc welding using DC supply
ANSWER:-4
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MACHINE'S QUESTIONS

Q1:-Voltage regulation of an alternating may be negative where

        1.       The load pf is lagging
        2.       The load pf is leading
        3.       It is loaded beyond its full oad capacity
        4.       The m/c is run at very low load

ANSWER:-2

Q2:-Power t/f are designed such that max efficiency occurs at

1.       Half of the full load
2.       Near the full load
3.       1/4th of the full load
4.       3/4th of the full load(75%)
ANSWER:-4


Q3:- The brushes of a dc m/c should be physically placed on the

1.       Armature in the polar axis
2.       Armature in the interloper axis
3.       Commutation in the polar  axis
4.       Commutator in the interpoler axis
ANSWER:-3

Q4:-V curve for isolated 3-pahse synchronous motor show

1.       The variation of mechanical  power with field excitation at constant speed
2.       The variation of armature voltage with field excitation at constant mechanical power
3.       The variation of armature voltage with mechanical power
4.       The variation of armature current with field excitation at constant mechanical power
ANSWER:-4

Q5:-Which of the following is correct?

1.       Synchronous motor is supplied with dc voltage in the armature winding
2.       Synchronous motor is supplied with ac voltage in the field winding
3.       Synchronous  motor is supplied with rectified voltage in the field winding
4.       Synchronous motor is supplied with rectified voltage in the armature winding

ANSWER:-4

Q6:-During stating of 3-phase I.M. the m/c may refuse to start at all this phenomena is called

1.       Singe phase
2.       Cogging
3.       Staing
4.       Crawing

ANSWER:-2

Q7:- In arc welding the voltage required to maintain the arc is in range

1.       200-2501V
2.       1000-1200V
3.       3.2-5V
4.       20-30V

ANSWER:-4
Q8:-Which of the following equipments has the lowest pf

1.       Fully loaded I.M.
2.       Immersion heater
3.       Incandescent lamp
4.       Arc lamp

ANSWER:-4
Q9:-The mmf produced by interpole is proportional to

1.       Field current
2.       Armature current
3.       Armature current
4.       i/p field current

ANSWER:-2
Q10:- Lumen is the unit of

1.       candela
2.       amp
3.       fulorcent flux
4.       stater
ANSWER:-3
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Thursday, July 7, 2016

Junior Engg. Paper Set

Q1:- The magnitude of AT required to establish a given value of flux in the air gap will be much greater than that required for Ion part of a magnetic circuit because

  1. air is a gas
  2. iron has the lowest permeability
  3. air has the lowest relative permeability 
  4. air is a good conductor of magnetic flux
ANSWER:-3

 Q2:- A linear circuit is one whose parameters

  1. change with change in voltage
  2. do not change with voltage and current
  3. change with change in current 
  4. all
ANSWER:-2

 Q3:-Moving coil instruments works on 

  1. dc only
  2. ac only
  3. both ac and dc 
  4. none
ANSWER:-1

 Q4:- Moving coil instruments also known as

  1. PMMC
  2. moving iron type
  3. both
  4. none
ANSWER:-1

 Q5:- Moving coil instruments can not use to measure

  1. ac current
  2. higher amp current
  3. dc current both 1 and 2 
  4. dc current
ANSWER:-3

 Q6:- Moving iron instrument has type

  1. attraction type
  2. repulsion type 
  3. both 
  4. none 
ANSWER:-3

 Q7:- Moving iron instrument work on 

  1. ac 
  2. dc 
  3. both
  4. none
ANSWER:-3

 Q8:- Which of the following motor is used in mixies ?

  1. reluctance motor
  2. repulsion motor
  3. hysteresis motor
  4. universal motor
ANSWER:-4

 Q9:- In bipolar junction transistors the type of configuration which will give both voltage gain and current gain is 

  1. CC
  2. CB
  3. CE
  4. none 
ANSWER:-3
Q10:- An active element in a circuit is one which

  1. dissipates energy
  2. receives energy
  3. both receives and supplies 
  4. supplies energy
ANSWER:-4
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MACHINE QUESTION

Q1:-The highest speed attainable by dc shunt motors is

     1.       Much higher than no loads speed
     2.       Much lower than no load speed
     3.       ideally infinite
     4.       Equal  to no load speed

ANSWER:-4


Q2:-A lap wound dc generator having 250. Armature conductor runs at 1200rpm if the generated emf is 200 V then the operating flux of the dc generator is

     1.       0.08 Wb
     2.       0.04 Wb
     3.       0.06 Wb
     4.       0.02Wb

ANSWER:-2


Q3:-which of the following is correct

     1.       The effect of air gap flux on armature current of a synchronous m/c is called armature reaction
     2.       The efficiency of current on main flux of a synchronous m/c is called armature reaction
    3.       The efficiency of armature current on air gap flux of a synchronous m/c is called armature reaction
    4.       The efficiency  of field current on main flux of a synchronous m/c is called armature reaction

ANSWER:-2

Q4:- If the starting torque of a 3-phase I.M. Tst for DOL starting  that for star delta starting of the same motor is

     1.       Tst/3
     2.       3Tst
     3.       Root 3 Tst
     4.       Tst/root 3

ANSWER:-1

Q5:- The motor characteristics best suited for traction purpose are those of

     1.       Dc series motor
     2.       Synchronous motor
     3.       Induction motor
     4.       Dc shunt motor

ANSWER:-1

Q6:- Star- delta stating of 3-phase of I.M. the starting voltage is reduced to

     1.       Root 3 times of normal voltage
     2.       3 times of normal voltage
     3.       1/3 times of norma voltage
     4.       (1/root 3 ) times of normal voltage

ANSWER:-4

Q7:-Which of the following does not employ a null method of measurement

     1.       Megger
     2.       Dc potentiometer
     3.       Kelvin double bridge
     4.       Ac potentiometer

ANSWER:-1


Q8:-Megger is an instrument by which we can measure

       1.       High resistance
       2.       Low resistance
       3.       High current
       4.       High voltage

ANSWER:-1

Q9:- With the decrease in the strength of the permanent magnet in an insulator megger due to ageing the megger reading will

      1.       Be lower than actual
      2.       Be higher than actual
      3.       Remain unaffected
      4.       Fluctate  rapidly

ANSWER:-1


Q10:- The burden of current transformer is expressed in

      1.       Watt
      2.       VA  
      3.       Rated secondary current
     4.       Voltage ating of secondary

ANSWER:-2
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Wednesday, July 6, 2016

MACHINE'S QUESTIONS

Q1:-The highest speed attainable by dc shunt motors is

           1.       Much higher than no loads speed
           2.       Much lower than no load speed
           3.       ideally infinite
           4.       Equal  to no load speed
ANSWER:-4

Q2:-A lap wound dc generator having 250. Armature conductor runs at 1200rpm if the generated emf is 200 V then the operating flux of the dc generator is

         1.       0.08 Wb
         2.       0.04 Wb
         3.       0.06 Wb
         4.       0.02Wb

ANSWER:-2

Q3:-which of the following is correct

        1.       The effect of air gap flux on armature current of a synchronous m/c is called armature reaction
        2.       The efficiency of current on main flux of a synchronous m/c is called armature reaction
        3.       The efficiency of armature current on air gap flux of a synchronous m/c is called armature reaction
        4.       The efficiency  of field current on main flux of a synchronous m/c is called armature reaction

ANSWER:-2

Q4:- If the starting torque of a 3-phase I.M. Tst for DOL starting  that for star delta starting of the same motor is

        1.       Tst/3
        2.       3Tst
        3.       Root 3 Tst
        4.       Tst/root 3

ANSWER:-1


Q5:- The motor characteristics best suited for traction purpose are those of

       1.       Dc series motor
       2.       Synchronous motor
       3.       Induction motor
       4.       Dc shunt motor

ANSWER:-1


Q6:- Star- delta stating of 3-phase of I.M. the starting voltage is reduced to

      1.       Root 3 times of normal voltage
      2.       3 times of normal voltage
      3.       1/3 times of normal voltage
      4.       (1/root 3 ) times of normal voltage

ANSWER:-4


Q7:-Which of the following does not employ a null method of measurement

      1.       Megger
      2.       Dc potentiometer
      3.       Kelvin double bridge
     4.       Ac potentiometer

ANSWER:-1


Q8:-Megger is an instrument by which we can measure

      1.       High resistance
      2.       Low resistance
      3.       High current
      4.       High voltage

ANSWER:-1


Q9:- With the decrease in the strength of the permanent magnet in an insulator megger due to ageing the megger reading will

       1.       Be lower than actual
       2.       Be higher than actual
       3.       Remain unaffected
       4.       Fluctate  rapidly

ANSWER:-1


Q10:- The burden of current transformer is expressed in

       1.       Watt
       2.       VA
       3.       Rated secondary current
       4.       Voltage ating of secondary


ANSWER:-2
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