Multicore cables generally use________________?

Which of the following bus-bar schemes has the lowest cost?

A. Ring bus-bar scheme
B. Single bus-bar scheme
C. Breaker and a half scheme
D. Main and transfer scheme

For an overhead line, the surge impedance is taken as________________?

A. 20-30 ohms
B. 70—80 ohms
C. 100—200 ohms
D. 500—1000 ohms
E. none of the above

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

The phenomenon qf rise in voltage at the receiving end of the open-circuited or lightly loaded line is called the________________?

A. Seeback effect
B. Ferranti effect
C. Raman effect
D. none of the above

The minimum clearance between the ground and a 220 kV line is about_________________?

A. 4.3 m
B. 5.5 m
C. 7.0 m
D. 10.5 m

Which of the following distribution systems is more reliable?

A. Radial system
B. Tree system
C. Ring main system
D. All are equally reliable