Transmission and Distribution

The usual spans with R.C.C. poles are_______________?

A. 40—50 meters
B. 60—100 meters
C. 80—100 meters
D. 300—500 meters

Galvanised steel wire is generally used as______________?

A. stay wire
B. earth wire
C. structural components
D. all of the above

Which of the following materials is not used for transmission and distribution of electrical power________________?

A. Copper
B. Aluminium
C. Steel
D. Tungsten

The wooden poles well impregnated with creosite oil or any preservative compound have life_____________?

A. from 2 to 5 years
B. 10 to 15 years
C. 25 to 30 years
D. 60 to 70 years

If variable part of annual cost on account of interest and depreciation on the capital outlay is equal to the annual cost of electrical energy wasted in the conductors, the total annual cost will be minimum and the corresponding size of conductor will be most economical. This statement is known as___________________?

A. Kelvin’s law
B. Ohm’s law
C. Kirchhoffs law
D. Faraday’s law
E. none of the above

Overhead system can be designed for operation up to____________?A. 11 kV
B. 33 kV
C. 66 kV
D. 400 kV

 

The underground system cannot be operated above_________________?

A. 440 V
B. 11 kV
C. 33 kV
D. 66 kV

_______________are the conductors, which connect the consumer’s terminals to the distribution?

A. Distributors
B. Service mains
C. Feeders
D. None of the above

By which of the following systems electric power may be transmitted ?

A. Overhead system
B. Underground system
C. Both A. and (b)
D. None of the above

When a live conductor of public electric supply breaks down and touches the earth which of the following will happen?

A. Current will flow to earth
B. Supply voltage will drop
C. Supply voltage will increase
D. No current will flow in the conductor
E. None of the above