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

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

The input impedance of a short circuited loss less transmission line of characteristic impedance 50 Ohm is may be capacitive or inductive depending on the length of the line

## Related questions

The magnitude of the open-circuit and short circuit input impedance of a transmission line are 100 ohm and 25 ohm respectively. The characteristic impedance of line is:  (1) 25 ohm (2) 50 ohm (3) 75 ohm (4) 100 ohm

A loss less line of characteristic impedance Z0 is terminated in pure reactance of –jZ0 value. VSWR is  (1) 10 (2) 2 (3) 1 (4) Infinity

A loss less transmission line having Surge Impedance Loading (SIL) of 2280 MW is provided with a uniformly distributed series capacitive compensation of 30%. Then, SIL of the compensated transmission line will be (A) 1835 MW (B) 2280 MW (C) 2725 MW (D) 3257 MW

For a transmission line open circuit and short circuit impedances are 20 Ω and 5 Ω. Then characteristic impedance is: (1) 100 Ω (2) 50 Ω (3) 25 Ω (4) 10 Ω

A 10 km long line has a characteristic impedance of 400 ohms. If line length is 100 km, the characteristic impedance is: (1) 4000 Ω (2) 400 Ω (3) 40 Ω (4) 4 Ω

When an antenna of input resistance 73 ohm is connected to a 50-ohm line and if the losses are ignored then its efficiency will be nearly   (A) 0.19 (B) 0.81 (C) 0.97 (D) 1.19

A transmission line is terminated at its characteristic impedance. The reflection coefficient is  (a) 1 (b) –1 (c) 0 (d) ∞

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 loss less line terminated with its surge impedance has

A single-phase transmission line of impedance j 0.8 ohm supplies a resistive load of 500 A at 300 V. The sending end power factor is?

A transmission line has 1 P.0 impedance on a base of 11 KV, 100 MVA. On a base of 55 KV. it will have a P.0 impedance of

The power loss in a transmission line depends on (a) current in the line. (b) resistance of the line. (c) length of the line. (d) All of the above

The reflection coefficient of a short-circuited line for voltage is: A) -1 B) +1 C) 0.5 D) zero

Corona loss is less when the shape of conductor is:

The lossless line of characteristics impedance 300 Ohm is terminated in a pure resistance of 200 Ohm. The value of the standing wave ratio is  (a) 1.5 (b) 0.67 (c) 1.0 (d) 1.25

If the RF transmission is terminated in its Characteristic impedance Z, which of the following statements is wrong : a. The input impedance of transmission line becomes Zc. b. The transmission line acts as an infinite long transmission line. c. The VSWR becomes one d. The VSWR becomes infinite

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

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

For a short transmission line with r/x ratio of is 1.0, the regulation will be zero when the load power factor is

A 50Ω transmission line is terminated in an impedance of 20-j50. What will be the reflection coefficient? A) 0.69 B) 1.69 C) 6.9 D) 16.9

Surge impedance loading (SIL) of power transmission line is the power delivered to a purely (a) inductive (b) capacitive (c) resistive load equal to surge impedance (d) none of these

A 100 km long transmission line is loaded at 110 kV.if the loss of line is 5 MW and the load is 150 MVA, the resistance of the line is?

The ratio of air-gap line voltage from open-circuit characteristic and armature current from short-circuit characteristic for a particular value of the field current in a synchronous generator is (A) synchronous reactance (B) synchronous impedance (C) unsaturated synchronous reactance (D) unsaturated synchronous impedance

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

A 220 kV, 3 phase transmission line is 60 km long. The resistance is 0.15 ohm / km and the inductance is 1.4 mH / km. Use the short line model to find the power at the sending end when the line is supplying a three phase load of 300 MVA at 0.8 pf lagging at 220 kV.  (A) 5.58MW (B) 80MW (C) 85.58MW (D) 74.42 MW

The inductance of a power transmission line increases with (A) decrease in line length. (B) increase in conductor diameter. (C) increase in spacing between phase conductors. (D) increase in load current carried by conductors.

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

When the load on a transmission line is equal to the surge impedance loading  (a) The receiving end voltage is less than the sending end voltage  (b) The sending end voltage is less than the receiving end voltage  (c) The receiving end voltage is more than the sending end voltage  (d) The receiving end voltage equal to the sending end voltage

A balanced Delta connected load supplied with 440 V 50 Hz three phase AC supply has R=10 Ohm and L=0.6 mH in is each arm. Calculate line and phase current, active power.

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

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

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

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

A long overhead transmission line is terminated by its characteristic impedance. Under this operating condition, the ratio of the voltage to the current at different points along the line will?

Surge impedance of overhead transmission line is normally in the order of (a) 1- 5 ohms (c) 300 - 500 ohms (b) 20 - 30 ohms (d) 300000 - 500000 ohms

A three phase 50 Hz, 400 kV transmission line is 300 km long. The line inductance is 0.97 mH/km per phase and capacitance is 0.0115 mF/km per phase. Assume a loss less line. Determine the line wavelength (a line phase constant).  (A) 1250 km (B) 6578 km (C) 4990 km (D) 2445 km

The secondary of a current transformer is always short-circuited under operating conditions because it?

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)

Stability of a transmission line can be increased by

The impedance Z offered by transmission line for a travelling wave which damps out the low frequency oscillation rapidly is also called

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

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

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

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