JVVNL Technical Helper Important MCQs In English-02

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

(A) Unbiased 

(B) Forward biased 

(C) Reverse biased 

(D) None of these 

Ans – (B)

8. A half wave rectifier is suitable only for

(A) Car radios 

(B) Battery charging 

(C) Variable speed AC Motors

(D) Electroplating 

Ans – (B)

9. LCD stands for……… 

(A) Logical Code display 

(B) Light Crystal diode

(C) Liquid Crystal Display 

(D) Logical Character display

Ans – (C)

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)