Material Science 11

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Electrical Engineering MCQ Question Papers: Campus Placement

Subject: Material Science 11

Part 5: List for questions and answers of Material Science

 

Q1. A constant voltage source has

a) low internal resistance

b) high internal resistance

c) minimum efficiency

d) minimum current capacity

 

Q2. Which among these is not the component of over head transmission lines?

a) Conductors

b) Cross arms

c) Danger plates

d) Transformers

 

Q3. Which among these properties is not suited for the conductor material?

a) High electrical conductivity

b) High specific gravity

c) Lower cost

d) High tensile strength

 

Q4. What is the empirical formula to calculate the number of strands?

a) 3n (n+2n) + 2

b) 3n (n+1) + 2

c) 3n (n+1) + 1

d) 3n (3+ 3n) + 1

 

Q5. The most ideal material for the over head conductor is copper. What are the advantages of this?

a) Smaller cross sectional area

b) Area offered by the wind loads is reduced

c) The price of copper is less

d) Both (a) and (b)

 

Q6. Which among the following properties has got a higher value for aluminium in comparison to that of copper?

a) Electrical resistivity

b) Melting point

c) Thermal conductivity

d) Specific gravity 

 

Q7. Why are galvanised steel conductors not suitable for transmitting large power over long distance?

a) Poor conductivity

b) High resistance of steel

c) More power loss

d) Both (a) and (b)

 

Q8. Why are the conductors used for higher voltage transmission stranded?

a) Ease of handling

b) Cheaper cost

c) Reduced resistivity

d) Increase in tensile strength

 

Q9. Which material is used for the manufacture of ground wire?

a) Aluminium

b) Galvanised steel

c) Cast iron

d) Stainless steel

 

Q10. When steel is reinforced what happens to the composite conductor?

a) 35 % more compared with equivalent weight of copper

b) 25 % more compared with equivalent weight of copper

c) 25 % less compared with equivalent weight of copper

d) 35 % less compared with equivalent weight of copper

 

Q11. Why is A.C.S.R conductor used as the replacement or substitute for copper?

a) Higher current carrying capacity

b) Economy

c) Being less weight

d) Higher tensile strength

 

Q12. What is the function of steel wire in A.C.S.R conductors?

a) Compensate for skin effect

b) Takes care of surges

c) Reduced capacitance and inductance

d) Provide additional mechanical strength 

 

Q13. Why grease is put between steel and aluminium conductors?

a) To reduce the corrosion by electrolytic action

b) To reduce friction between the strand

c) To eliminate the air gaps

d) To reduce the leakage of current

 

Q14. What is the general ratio of the cross sectional area of the two metals used in the A.C.S.R conductors?

a) 1:8

b) 1:4

c) 4:3

d) 2:1

 

Q15. For high voltage transmission lines, why are conductors suspended from towers?

a) Increase the clearance from ground

b) Reduce clearance from ground

c) Take care of increase in length

d) Reduce the environmental effects

 

Q16. In India, which types of poles are commonly used for distribution?

a) Wooden poles

b) RCC poles

c) Steel poles

d) Both (b) and (c)

 

Q17. Which among these are the properties for the line supports?

a) Higher mechanical strength

b) Light in weight

c) Easy accessibility of conductors for maintenance

d) All of these

 

Q18. What is the maximum permissible limit of voltage for the line supports?

a) 30 kV

b) 20 kV

c) 11 kV

d) 44 kV 

 

Q19. To prevent rotting oil the wooden poles which oil is impregnated to it?

a) Kerosene oil

b) Mineral oil

c) Creosote oil

d) All the above

 

Q20. Steel poles are painted so as to prevent it from

a) Corrosion

b) Borer

c) Termites

d) All of these 

 

Part 5: List for questions and answers of Material Science

 

Q1. Answer :a

 

Q2. Answer :d

 

Q3. Answer :b

 

Q4. Answer :c

 

Q5. Answer :d

 

Q6. Answer :a

 

Q7. Answer :d

 

Q8. Answer :a

 

Q9. Answer :b

 

Q10. Answer :c

 

Q11. Answer :b

 

Q12. Answer :d

 

Q13. Answer :a

 

Q14. Answer :b

 

Q15. Answer :a

 

Q16. Answer :d

 

Q17. Answer :

 

Q18. Answer :b

 

Q19. Answer :c

 

Q20. Answer :a