The voltages at the two ends of a line are 132 KV and its reactance is 40 ohms. The capacity of the line is

A.      435.6 MW

B.      217.5 MW

C.      251.5 MW

D.      500 MW

A Mho relay is

A.      Voltage restrained directional relay

B.      Voltage restrained over current relay

C.      Directional restrained over current relay

D.      None of the above

A Impedance relay is

A.      Voltage restrained directional relay

B.      Voltage restrained over current relay

C.      Directional restrained over current relay

D.      None of the above

The most economical load on an overhead line is

A.      Greater than the natural load

B.      Less than the natural load

C.      Equal to the natural load

D.      None of the above is necessary

The most economical load on underground cable is

A.      Greater than the surge loading

B.      Less than the surge loading

C.      Equal to the surge loading

D.      None of the above is necessary

Mho relay is normally used for protection of

A.      Long transmission line

B.      Short transmission line

C.      Medium transmission line

D.      No length criteria

Reactance relay is normally preferred for protection against

A.      Earth fault only

B.      Phase fault only

C.      None of the above

If the fault current is 2000 amps, the relay setting 50% and the C.T. ratio is 400/5, then the plug setting multiplier will be

A.      25 A

B.      15 A

C.      50 A

D.      10 A

For a load flow solution the quantities normally specified at the voltage controlled bus are

A.      P and Q

B.      P and ǀVǀ

C.      Q and ǀVǀ

D.      P and δ

Answer :     P and ǀVǀ

The surge impedance of 50 miles long underground cable is 50 Ohms. For a 25 Miles length it will be.

A.      25 Ohms

B.      50 Ohms

C.      100 Ohms

D.      None of the Above

Answer : 50 Ohms

Bundled conductors are used for EHV transmission lines primarily for reducing the

A)     Corona loss

B)      Surge impedance of the line

C)      Voltage drop across the line

D)     Copper loss

Installation of capacitors at suitable locations and of optimum size in a distribution system results in

I. Improved voltage regulation.
II. Reduction in distribution power losses.
III. Reduction of KVA rating of distribution transformers.
Select the correct answer using codes given below:

A)     1 alone

B)      1 and 2

C)      1,2 and 3

D)     3 alone

In a three unit insulator string, voltage across the lowest unit is 17.5kV and string efficiency is 84.28%. the total voltage across the string will be equal to

A)     8.825 kV

B)      44.25 kV

C)      88.25 kV

D)     442.5 kV

The surge impedance of a 3 phase, 400kV transmission line is 400Ω. The surge impedance loading (SIL) is

A)     400 MW

B)      100 MW

C)      1600 MW

D)     200 MW

If a travelling-wave travelling along a loss-free overhead line does not result in any reflection after it has reached the far end, then the far end of the line

A)     Open circuited

B)      Short circuited

C)      Terminated in to a resistance equal to surge impedance of the line

D)     Terminated in to a capacitor

A travelling wave 400/1/50 means crest value of

A)     400 V with rise time 1/50 S

B)      400 kV with rise time 1 S and fall time 50S

C)      400 kV with rise time 1 µS with fall time 50µS

D)     400MV with rise time 1µS and fall time 50µS

Consider the following statements:Surge impedance loading of a transmission line can be increased by

I. Increasing its voltage level
II. Addition of lumped inductance in parallel
III. Addition of lumped capacitance in series
IV. Reducing the length of line
Which of these statements are correct?

A)     1 and 3

B)      1 and 4

C)      2 and 4

D)     3 and 4

The load current in short circuit calculation are neglected because

I. Short circuit currents are much larger than load currents
II. Short circuit currents are greatly out of phase with load currents
Which of these statements is/are correct?

A)     Neither 1 nor 2

B)      2 alone

C)      1 alone

D)     1 and 2

In pump storage hydropower plant, the electrical machine is made to work alternately as generator and motor. The efficiency of the generator working at the same electrical power level is

A)     Greater than that as motor

B)      Equal to that as motor

C)      Less than that as motor

D)     Greater or less than that as motor depending on the type of machine

In a thermal nuclear reactor

 I. The purpose of moderator is to slowdown fast neutrons produced due to fusion.
II. The moderator material must have low molecular weight.
III. Ordinary water can be used as moderator with natural uranium as fuel.
IV. The multiplication factor is kept slightly greater than unity during its normal functioning.
Which of these statements are correct?

A)     1 and 3

B)      3 and 4

C)      1,2 and 3

D)     1,2 and 4