JVVNL Technical Helper Important MCQs In English-02, We advise all the applicants to work hard for the preparations. We are here to help you with exam preparations. Here in our post, you will find JVVNL Technical Helper Important MCQs In English. We hope this will be helpful for all the candidates to prepare a strong groundwork for the Technical helper Exam.

JVVNL Technical Helper Important MCQs In English-02

1. MCB is more reliable than

(A) Switches 

(B) Fuses 

(C) Circuit breakers 

(D) Power sockets 

Ans – (B)

2. Thermal relays are often used in : 

(A) Motor starters 

(B) Transformer Protection

(C) Both (A) and (B) 

(D) None of these

Ans – (A)

3. You have to rewind a motor whose operating temperature is about 130° C. Which insulating material would you select ? 

(A) Fibre

(B) Mica 

(C) Cotton 

(D) Paper immersed in oil

Ans – (B)

4. The phase voltage of a star - connected, 3 - phase circuit is 230 V. The line voltage will be 

(A) 210 V 

(B) 220 V 

(C) 415 V

(D) 400 V 

Ans – (D)

5. A wire measuring one mm diameter has a cross sectional area of………. 

(A) One mm2 

(B) 0.78 mm2

(C) 0.87 mm2 

(D) None of these 

Ans – (C)

6. Which one of the following derived units of SI system is wrongly matched? 

(A) Force-Newton 

(B) Pressure - Pascal 

(C) Work- Volt 

(D) Magnetic Flux Density - Tesla 

Ans – (C)

7. A light emitting diode produces light when it is

10. Which of the following is the primary function of the fuse ? 

(A) To protect the operator

(B) To protect the line

(C) To prevent excessive current

(D) To open the circuit

Ans – (C)

 

11. The domestic voltage of 240V AC is called …………….voltage. 

(A) Low tension voltage

(B) High tension voltage

(C) Earth 

(D) Neutral 

Ans – (A)

12. What is the material used inside the breather to prevent moisture entering the transformer ? 

(A) Copper sulphate

(B) Sodium chloride 

(C) Sodium Silicate

(D) Silica gel 

Ans – (D)

13. What are the disadvantages of shaded pole motors ? 

(A) Low efficiency 

(B) Low starting torque 

(C) Very little overload capacity 

(D) All of these 

Ans – (D)

14. Which metal is used to provide strength to the lead acid battery plates ? 

(A) Zinc 

(B) Tin 

(C) Antimony 

(D) Copper

Ans – (C)

15. A moving iron ammeter reads 10 A. What is the peak current of the oscillation ? 

(A) 7.07 A 

(B) 1.414 A 

(C) 70.7 A 

(D) 28.2 A 

Ans – (D)

16. Single core cables are usually NOT provided with

(A) Sheath 

(B) Paper insulation 

(C) Steel armouring 

(D) Rubber insulation

Ans – (C)

17. On inspection, the Commutator of a DC generator was found badly worn out. Sand papering is of no use. The best thing to do is to 

(A) Turn the Commutator on a lathe 

(B) Clean the Commutator with CTC 

(C) Replace the Commutator 

(D) Replace the armature 

Ans – (A)

18. Scott connections are used to transform 

(A) Single phase supply into three phase 

(B) Single phase supply into two phase supply 

(C) Three phase supply into two phase supply

(D) Star connected primary into delta connected secondary 

Ans – (C)

19. Bending angle of the hard drawn bare copper conductor for Britannia joint should be : 

(A) 60° 

(B) 45° 

(C) 90° 

(D) 120° 

Ans – (C)

20. Which of the following transformer is used for supplying general power and lighting ? 

(A) Substation transformer

(B) Power transformer

(C) General purpose transformer 

(D) Distribution transformer

Ans – (D)

JVVNL Technical Helper Important MCQs In English-01, We advise all the applicants to work hard for the preparations. We are here to help you with exam preparations. Here in our post, you will find JVVNL Technical Helper Important MCQs In English. We hope this will be helpful for all the candidates to prepare a strong groundwork for the Technical helper Exam.

JVVNL Technical Helper Important MCQs In English-01

1. A substance that has a high retentivity can be used for the manufacture of…….

( A ) Electromagnet

( B ) Permanent magnets

( C ) Temporary magnets

( D ) Paramagnets

Ans – (B)

 

2. Which of the following has almost no change in resistance with temperature change?

( A ) Nickel

( B ) Nachrome

( C ) Aluminium

( D ) Manganin

Ans – (D)

3. If the size of the circuit copper conductor is 10 sq. mm, then the size of the earth conductor in G.I wire should be :

( A ) 1.5 sq. mm

( B ) 2.5 sq. mm

( C ) 15sq.mm

( D ) 10 sq.mm

Ans – (D)

4. Invertors converts

( A ) DC to AC

( B ) AC to DC

( C ) DC to DC

( D ) AC to AC

Ans – (A)

5. What is the normal voltage of a fully charged lead acid cell ?

( A ) 1.1 V

( B ) 2.2V

( C ) 1.15V

( D ) 13V

Ans – (B)

6. A material that is slightly repelled by a magnet is called

( A ) Magnetic

( B ) Paramagnetic

( C ) Diamagnetic

( D ) Ferromagnetic

Ans – (C)

7. The rectifier is used to convert 

( A ) AC to DC

( B ) DC to AC

( C ) Pulsating current to alternating current

( D ) Both ( A ) and ( B )

Ans – (A)

 

8. Cooling of transformer is necessary to

( A ) Increase the efficiency

( B ) Reduce the losses

( C ) Reduce humming

( D ) Dissipate the heat

Ans – (D)

 

9. An AC the circuit has 40 ohms of resistance, 90 ohms of inductive reactance and 60 ohms of capacitive reactance. Then the impedance is equal to

( A ) 50 ohms

( B ) 70 ohms

( C ) 210 ohms

( D ) 190 ohms

Ans – (A)

 

10. The fuse operates due to the……………effect of current

( A ) Magnetic

( B ) Electrostatic

( C ) Heating

( D ) None of these

Ans – (C)

 

11. What is the inter-layer insulation for small transformers?

( A ) Mica

( B ) Butter paper

( C ) Leatheroid paper

( D ) Varnish

Ans – (B)

 

12. An insulated conductor used in a switchboard shall be…..

( A ) Listed

( B ) Flame retardant

( C ) Rated not less than the voltage applied to other conductors or busbars with which it may come in contact 

( D ) All of these

Ans – (D)

 

13. A motor has become thoroughly wet because of exposure to heavy rains. Before operating the motor, it is necessary to dry it out by

( A ) Wiping it dry with a clean cloth

( B ) Keeping it under a ceiling fan

( C ) Blowing hot air by using air blower

( D ) Placing it in an Ovens

Ans – (D)

 

14. For a circuit rated for 5 Amps, the correct tinned copper wire size will be

( A ) 35 SWG

( B ) 36 SWG

( C ) 37 SWG

( D ) 38 SWG

Ans – (A)

15. Base and covers of the wiring accessories are made of

( A ) Ignitable material

( B ) Non-ignitable material

( C ) Conductive material

( D ) Heat resistive material

Ans – (B)

16. Phase relationship between the applied voltage and the current flowing through the inductive circuit is

( A ) Current leads the voltage

( B ) Voltage lags the current

( C ) Current lags the voltage

( D ) Current in phase with the voltage

Ans – (C)

17. The illumination required for a work place where fine work is performed will be in the order of

( A ) 500 lumens/sq. meter

( B ) 1000 lumens/sq. meter

( C ) 1500 lumens/sq. meter

( D ) 2000 lumens/sq. meter

Ans – (C)

18. The capacitor used in a fan motor is connected in

( A ) Parallel with starting winding

( B ) Parallel with starting and running winding

( C ) Series with the starting winding

( D ) Series with starting and running winding

Ans – (C)

19. Power companies are interested in improving the power factor to

( A ) Reduce the line current  

( B ) Increase the motor efficiency

( C ) Increase the volt-amperes

( D ) Decrease the power

Ans – (A)

20. In cables, the thickness of the layer of insulation on the conductor depends upon

( A ) Current capacity

( B ) Voltage

( C ) Power factor

( D ) Reactive power

Ans – (B)