# If diameter of the conductor is 0.1 cm, then what is the inductance of a 3Φ line operating at 50 Hz and conductors are arranged as follows

1.  2.15 mH/km

2.  1.25 mH/km

3.  1.29 mH/km

4.  1.84 mH/km

4

1.84 mH/km

Explanation :
No Explanation available for this question

# A three phase 50Hz line consists of three conductors each of diameter 21 mm. The spacing between conductors is as shown. The inductance per phase per km of the line will be

1.  12.2 x 10-1 H/km

2.  8.2 x 10-4 H/km

3.  5.6 x 10-3 H/km

4.  none of these

4

12.2 x 10-1 H/km

Explanation :
No Explanation available for this question

# Two arrangements of conductors are proposed for a 3-phase transmission line one with equilateral spacing of 4 m and the other, a flat with 4rn between the conductors, as shown in the given figure. The Conductor, diameter in each case is 2 cm. Assuming that the line is transposed in both cases which one of the following statements would b true (C-;, = capacitance in F/in line to neutral, L =inductance in H /m per phase)

1.  Cn 1=Cn2 and L1>L2

2.  Cn1>Cn2 and L1>L2

3.  Cn1L2

4.  Cn1>Cn2 and L1=L2

4

Cn1>Cn2 and L1=L2

Explanation :
No Explanation available for this question

# The load duration curve for a system is shown in the figure below. The load factor will be

1.  0.83

2.  0.96

3.  0.67

4.  0.50

4

0.83

Explanation :
No Explanation available for this question

# A transmission line conductor having a diameter of 19.5 mm, weight 850 kg/km. Span is 275 m. Wind pressure is 39 kg/m2, of projected area with ice coating of 13 mm. Ultimate strength of the conductor is 8000 kg. What is the maximum sag, if factor of safety is 2 and ice weight 910 kg/m3

1.  4.5 m

2.  6.4 m

3.  7 .0 m

4.  5 m

4

6.4 m

Explanation :
No Explanation available for this question

# What is the inductance of the double circuit line shown in the given figure The self GMD of the conductors is 0.0069 m.

1.  2.93 mH/km

2.  0.613 mH/km

3.  0.590 mH/km

4.  1.21 mH/km

4

0.613 mH/km

Explanation :
No Explanation available for this question

# A single phase load of 100 kVA is delivered at 2000 V over a transmission line having R = 1.4Ω, X = 0.8Ω. The voltage at the sending, when power factor of the load is unity, will be

1.  1.68 kV

2.  2.980 kV

3.  2.84 kV

4.  2.069 kV

4

2.069 kV

Explanation :
No Explanation available for this question

# A three phase, 50 Hz transmission line 80 km long delivers, 72mW at 0.8 pf lagging at 60 kV (phase). The line constant per Conductor are R = 2.5Ω, L = 0.2H, C = 0.5 F. Shunt leakage are neglected. The efficiency and regulation of the line will be

1.  24%, 98%

2.  98%, 24%

3.  95%, 20%

4.  78%, 2%

4

98\%, 24\%

Explanation :
No Explanation available for this question

# A conductor with 2.4 cm diameter is passed centrally through a porcelain bushing €r = 3 having internal and external diameters of 3 cm and 9 cm respectively The voltage between the conductor and an earthed clamp surrounding the porcelain is 20 kVrms. The corona will be present in air space round the conductor.

1.  Yes

2.  No

3.  Cannot say

4.  data insufficient

4

Yes

Explanation :
No Explanation available for this question

# Series capacitive compensation in EHV transmission lines is used to

2.  improve the stability of the system

3.  reduce the voltage profile

4.  improve the protection of the line

4