1. A 240 kV 2μs rectangular pulse surge on a transmission line has surge impedance of 350 ohms. It approaches a generating station with capacitance of 3000 pF. The transmitted voltage will be ____________
a) 340.5 kV
b) 280 kV
c) 400 kV
d) 480 kV
Explanation: Vt = 2Vi(1-e(-t/Zc)) = 2*240*1000(1-e-2*10-6/3*350*10-9).
2. In a transmission line system, the feeders act as input to _________
a) distributors
b) service mains
c) transformer sub stations
d) all of the mentioned
Explanation: The feeders have bulk power and they have no tappings. They feed to the distributors.
3. One needs to design the distributors, the parameter which will be considered for the design of it?
a) voltage drop in it
b) current flowing
c) operating voltage
d) operating frequency
Explanation: Distributors work based on the voltage drops measured across them.
4. One would design the feeders of the transmission system based on its ____________
a) current capacity
b) voltage drop
c) operating voltage
d) all of the mentioned
Explanation: Feeders do not have tappings and they are designed on the basis of current flowing through them.
5. The underground transmission and distribution of power is better than the corresponding overhead transmission and distribution in respect of _________
a) appearance and safety
b) maintenance cost
c) frequency of faults
d) appearance, safety, maintenance, frequency
Explanation: All the points are advantageous with respect to overhead transmission line in an underground power transmission system.
6. Before installing any transmission system, one has to decide about the type of the transmission system to be employed. Considering a monetary shortage and economical setup, one would take up _____________
a) underground system
b) overhead system
c) underground or overhead system
d) can be chosen randomly.
Explanation: Underground installation takes a lot of initial cost.
7. The volume of copper required in a transmission system is proportional to _________
a) voltage and power factor
b) power factor
c) voltage
d) current
Explanation: Weight of the copper is proportional to voltage and power factor.
8. While deciding an efficient and economical transmission and distribution system, the preferred distribution system will be _____________
a) single phase, 2 wire
b) two phase, 3 wire
c) three phase, 3 wire
d) three phase, 4 wire
Explanation: For a reliable system, the distribution system should be 4 wire, in case a fault occurs.
9. In India, the preferred poles used in the transmission and distribution is ______
a) Steel poles
b) RCC poles
c) Steel and RCC poles
d) Wood poles
Explanation: The most commonly used poles are steel and RCC poles.
10. Copper has got higher resistivity than aluminium which makes it less used in transmission system.
a) True
b) False
Explanation: Aluminium has higher resistivity over copper.