400 Important Transmission and Distribution MCQ Question and Answer | PDF Free Download
1.In HV transmission, the spacing between sub-conductors of a bundle is approximately
- A20 cm
- B40 cm
- C80 cm
- D3.5 cm
2.For a stranded conductor, the ratio of GMR to actual radius is
- AEqual to 1
- BMore than 1
- CEqual to 0.7788
- DLess than 0.7788
3.The bundled conductors in EHV transmission system provides
- AReduced capacitance
- BIncreased capacitance
- CIncreased inductance
- DIncreased voltage gradient
4.Which one of the following statements is not correct for use of bundled conductors in transmission lines?
- AControl of voltage gradient
- BReduction in corona loss
- CReduction in radio interference
- DIncrease in interference with communication lines
5.Bundled conductors are mainly used in high voltage overhead transmission lines to
- AReduce transmission line losses.
- BIncrease mechanical strength of the line.
- CReduce corona.
- DReduce sag.
6.Proximity effect
- AIs more pronounced for large conductors, high frequencies and close proximity.
- BIncreases the resistance of the conductors and reduces the self-reactance.
- CIs substantially eliminated with stranded conductors.
- DAll of the above
7.Capacitance in equivalent circuit of transmission line is due to
- ACurrent in the line.
- BDifference in potential of line.
- CLeakage of current.
- DPresence of magnetic flux.
8.If the separation between the three phases of transmission line in increased then
- AThe inductance will increase and capacitance will remain unchanged.
- BBoth the inductance and capacitance will increase.
- CThe inductance will increase and capacitance will decrease.
- DThe inductance will decrease and capacitance will increase.
9.The recharging reactance of 50 km length of the line is 1500 ohm. What is the charging reactance for 100 km length of the line?
- A1500 ohm
- B3000 ohm
- C750 ohm
- D600 ohm
10.Bundled conductors are used to
- AReduce inductance of the line.
- BReduce both inductance and capacitance.
- CReduce corona loss.
- DReduce corona loss and the line inductance
11.If the effect of earth is taken into account, then the capacitance of line to ground
- ADecreases
- BIncreases
- CRemains unaltered
- DBecomes infinite
12.For equilateral spacing of conductors of an untransposed 3-phase line, we have
- ABalanced receiving-end voltage and no communication interference.
- BUnbalanced receiving-end voltage and no communication interference.
- CBalanced receiving-end voltage and communication interference.
- DUnbalanced receiving-end voltage and communication interference.
13.Transmission lines are transposed to
- AReduce corona loss.
- BReduce skin effect.
- CPrevent interference with neighbouring telephone lines.
- DPrevent short-circuit between any two lines.
14.Transposition of Transmission line is done to
- AReduce line loss.
- BReduce skin effect.
- CBalance line voltage drop.
- DReduce corona
15.High voltage Transmission lines are transposed because
- ACorona losses can be minimized.
- BComputation of inductance becomes easier.
- CVoltage drop in the lines can be minimized.
- DPhase voltage imbalances can be minimized.
16.The concept of an electrically short, medium and long line is primarily based on the
- ANominal voltage of the line.
- BPhysical length of the line.
- CWavelength of the line.
- DPower transmitted over the line.
17.Which of the following is neglected while analyzing a short transmission line?
- AShunt admittances.
- BPower losses.
- CSeries impedance.
- DNone the above.
18.The line resistance and inductance are only considered in modelling the equivalent circuit of a short length overhead transmission line because line capacitance to ground is
- AEqual to zero
- BFinite but very small
- CFinite but very large
- DInfinite
19.Which of the following voltage regulation is considered to be the best for transmission lines?
- A2%
- B30%
- C70%
- D98%
20.If in a short transmission line, resistance and inductive reactance are found to be equal and regulation appears to be zero, then the load will
- AHave unity power factor
- BHave zero power factor
- CBe 0.707 leading
- DBe 0.707 lagging