A 3-phase 4 wire system is commonly used on________________?

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

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

Transmitted power remaining the same, if supply voltage of a D.C. 2-wire feeder is increased 100 percent, saving in copper is____________________?

A. 25 percent
B. 50 percent
C. 75 percent
D. 100 percent

The angular displacement between two interconnected stations is mainly due to___________?

A. armature reactance of both alternators
B. reactance of the interconnector
C. synchronous reactance of both the alternators
D. all of the above

Which of the following is the demerit of a ‘constant voltage transmission system’ ?

A. Increase of short-circuit current of the system
B. Availability of steady voltage at all loads at the line terminals
C. Possibility of better protection for the line due to possible use of higher terminal reactants
D. Improvement of power factor at times of moderate and heavy loads
E. Possibility of carrying increased power for a given conductor size in case of long-distance heavy power transmission

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

High voltage transmission lines use__________________?

A. suspension insulators
B. insulators
C. both A. and B.
D. none of the above