# In an AC transmission line difference in phase of voltage at two ends of the line is due to

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In an AC transmission line difference in phase of voltage at two ends of the line is due to (a) System voltage (b) Insulators (c) Resistance of line (d) Reactance of line

## Related questions

If voltage at the two ends of a transmission line is 132 kV and its reactance is 40 Ohms, the capacity of the line will be: (A) 435.6 MW (B) 217.8 MW(C) 251.5 MW (D) 500 MW

A transmission line is operating with a Phase shift of 80° between two ends. If the load is suddenly increased A) The phase displacement will increase B) The phase displacement will decrease C) The phase displacement will not change D) The surge impedance will increase

In long AC transmission lines, the receiving end voltage becomes greater than sending end voltage at light load or no load operation. This is due to (a) Ferranti effect (b) Skin effect (c) Proximity effect (d) Corona effect

Galloping in transmission line conductors arises generally due to - (A) asymmetrical layer of ice formation (B) vortex phenomenon in light winds (C) heavy weight of line conductors (D) adoption of horizontal conductor

The inductance of single phase two wire power transmission line per km gets doubled when the  (a) Distance between wires is doubled  (b) Distance between the wires is increased four fold  (c) Distance between the wires is increased as square of the original distance  (d) Radius of the wire is doubled

The main consideration for operating transmission line at high voltage is (a) to increase efficiency only. (b) to reduce power loss only. (c) to increase power transmission capability only. (d) All of the above

Effect of increase in temperature in an overhead transmission line is (a) to increase stress and length both (b) to decrease stress and length both (c) to decrease stress and increase length (d) None of the above

An overhead transmission line has a span of 260 m. The weight of the conductor is 0.68 kg/m. The maximum allowable tension in the line is 1550 kg. Maximum sag of the line should be (a) 5.8 m (b) 4.6 m (c) 2.7 m (d) 3.7 m

Why are shunt reactors connected at the receiving end of long transmission line system: (1) To increase the terminal voltage (2) To compensate voltage rise caused by capacitive charging at light load (3) To improve power factor (4) None of these

What type of insulator will be used if the direction of the transmission line is to be changed?

Which of the following is used for power factor improvement in transmission line ? (a) Three phase induction (b) An overexcited three phase synchronous motor running on no load (c) Three phase AC series motor (d) Choke

Is the power line voltage available in our homes a dc or an ac voltage?

If 3000 kW power is to be transmitted over a distance of 30 km, the desirable transmission voltage will be.  (A) 11 kV (B) 33 kV (C) 66 kV (D) 132 kV

The corona loss of a 3-phase transmission line is 100 kW at 60 kV/phase and 25 kW at 50 kV/phase. The disruptive critical voltage is (A) 40 kV (B) 43.6 kV (C) 49.6 kV (D) 50 kV

A transmission line to be reciprocal, the condition is (a) A = D (b) AC – BD = 1 (c) AD – BC = 1 (d) AB – CD = 1

Earth wire on EHV overhead transmission line is provided to protect the line against:

If the transmission line is loaded with leading reactive volt amperes, there will be rise of voltage at the receiving end and this (a) increases (b) decreases (c) remains same with the increase in the length of line (d) none of these

An R-L series AC circuit has R = 10 ohm and XL = 10 ohm. It is connected to an AC voltage source, the phase angle between voltage and current is (a) 30° (b) 45° (c) 60° (d) 36.8°

In AC system, the voltage drops are due to (1) Resistance (2) Inductance (3) Capacitance (4) All of the above

The severity of line to ground and three phase faults at the terminals of an unloaded synchronous generator is to be same. If the terminal voltage is 1.0 pu, Z1=Z2=j0.1 p.u. and Z0= j0.05 p.u. for the alternator, then the required inductive reactance for neutral grounding is   (a) 0.05 p.u. (b) 0.0166 p.u. (c) 0.1 p.u. (d) 0.15 p.u.

In order to reduce the harmful effects of harmonics on the AC side of a high voltage DC transmission system_____ are provided. (A) synchronous condensers (B) shunt capacitors (C) shunt filters (D) static compensators

In a transmission line if booster transformers are to be used, preferred location will be  (A) At the receiving end (B) At the sending end (C) At the intermediate point (D) Anywhere in the line

What is the difference between line and phase voltage?

For extra high voltage ac transmission lines, conductors used are (a) All aluminium (b) All steel (c) AAAC (d) ACSR

In an alternator at lagging power factor the generated voltage per phase as compared to that at unity power factor?

For an existing ac transmission line, the string efficiency is 80%, if dc voltage is supplied for the same setup, the string efficiency will be?

An 800 kV transmission line has a maximum power transfer capacity of P. If it is operated at 400 kV with the series reactance unchanged, the new maximum power transfer capacity is approximately (A) P (B) 2P (C) P / 2 (D) P / 4

The presence of earth in case of overhead transmission line (a) increases capacitance (b) increases inductance (c) decreases capacitance (d) decreases inductance

how the booster is connected in transmission line ?

Voltages phasors at the two terminals of a transmission line of length 70 km have a magnitude of 1.0 per unit but are 180 degree out of phase. Assuming that the maximum load current in the line is 1/5th of minimum 3-phase fault current. Which one of the following transmission line protection schemes ... pick up at 1.25 times the maximum load current (C) Pilot relaying system with directional comparison scheme (D) Pilot relaying system with segregated phase comparison scheme

How many insulator disc used for 33 kV transmission voltage line?

The sending and receiving end voltages of a three phase transmission line at 100 MW load are equal at 230 KV. The phase line impedance is j14 ohm. Calculate the maximum steady state power that can be transmitted over the line.  (A) 3778.5 MW (B) 2234.56 MW (C) 1784.19 MW (D) 512.37 MW

To increase power transfer capability of a long transmission line, we should:  (1) Increase line resistance (2) Increase transmission voltage (3) Decrease line reactance (4) Both (2) & (3)

Problem of instability of transmission line occurs due to excessive. a. Voltage drop b. Current drop c. Power drop d. None of above

Which of the following relations is true for long transmission line ? (a) VS = AVR – BIR (b) VS = BVR + AIR (c) VS = AVR + BIR (d) VS = BVR – AIR

If diameter of each conductor of a transmission line is ‘d’, then the diameter of n-layer stranded conductor will be (a) (2n – 1) d (b) (2n + 1) d (c) (3n – 1) d (d) (3n + 1) d

The input impedance of a short circuited loss less transmission line of characteristic impedance 50 Ohm is

The function of the earth wire in an extra high voltage line is to?

The resolved part of the resultant of two forces inclined at an angle 9 in a given direction is equal to

A two-phase generator is connected to two 90Ω load resistors. Each coil generates 120 V ac. The value of current flowing through the common neutral line will be: A. 1.33 A B. 1.88 A C. 2.66 A D. 1.77 A

In case the height of transmission tower is increased, which of the following parameter is likely to change?  (A) Resistance (B) Inductance (C) Capacitance (D) None of the above

The purpose of guard ring in transmission lines is to  (1) reduce the earth capacitance of the lowest unit. (2) increase the earth capacitance of the lowest unit. (3) reduce the transmission lines losses. (4) reduce the reactance of the line

A transmission line conductor at a river crossing is supported from two towers at height. of 30 m and 90m, above water level. The horizontal distance between the towers is 270m, if the tension in the conductor is 1800 kg and the conductor weight 1 kg/m. What is the clearance between the conductor and the water at a point midway between the towers?

The bundled conductor in EHV transmission line system provides (a) increased inductance (b) reduced capacitance (c) increased capacitance (d) increased voltage gradient