The regulation of Short Transmission lines depends up on
a) Distance of line
b) Frequency
c) Power factor
d) All

1 Answer

Answer :

Ans: Power factor

Related questions

Description : State the effects of low power factor on efficiency and voltage regulation of short transmission lines. 

Last Answer : i) Effect of Low power factor on efficiency:- When power factor of load reduces current drawn by transmission line increases so copper losses in transmission line increases, hence transmission ... increases, so voltage drop in transmission line increases so regulation increases. (Become Poor) 

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

Last Answer : For a short transmission line with r/x ratio of is 1.0, the regulation will be zero when the load power factor is 0.707 lead

Description : Which of the following is the demerit of a 'constant voltage transmission system' ? (a) Increase of short-circuit current of the system (b) Availability of steady voltage at all loads at ... of carrying increased power for a given conductor size in case of long-distance heavy power transmission

Last Answer : (a) Increase of short-circuit current of the system

Description : Which of the following is the demerit of a 'constant voltage transmission system' ? (a) Increase of short-circuit current of the system (b) Availability of steady voltage at all loads at ... of carrying increased power for a given conductor size in case of long-distance heavy power transmission

Last Answer : (a) Increase of short-circuit current of the system

Description : Which of the following statements concerning AC circuits is correct? A. The power factor of a resistive circuit is always zero. B. True power in an inductive circuit always equals apparent power. ... . D. Total opposition to the flow of alternating current depends upon the amount of reactive power.

Last Answer : Answer: C

Description : A transformer has negative voltage regulation when its load power factor is- (a) Zero (b) Unity (c) Leading (d) Lagging

Last Answer : Ans: C

Description : A resistor placed in parallel to the output of a power supply _____________. A. is a temperature compensator B. corrects power factor C. prevents excessive currents D. aids in output voltage regulation

Last Answer : Answer: D

Description : A two-winding single phase transformer has a voltage regulation of 4.5% at full-load and unity power-factor. At full-load and 0.80 power-factor lagging load the voltage regulation will be (A) 4.5%. (B) less than 4.5%. (C) more than 4.5%. (D) 4.5% or more than 4.5%.

Last Answer : (C) more than 4.5%.

Description : Transmission efficiency of transmission line increases with the: a) Decrease in power factor and voltage b) Increases in power factor and voltage c) Increase in power factor and decrease in voltage d) Increase in the voltage but decrease in the power factor

Last Answer : Ans: B

Last Answer : The velocity factor of a transmission line depends on relative permittivity of dielectric.

Description : The interaction between a transmission line and communication line is minimized by (a) transposing transmission as well as communication lines (b) increasing the height of the transmission line tower (c) increasing the distance between the two lines (d) all of the above

Last Answer : (d) all of the above

Description : Shunt capacitance is neglected while considering (a) short transmission line (b) medium transmission line (c) long transmission line (d) medium and long transmission lines

Last Answer : (a) short transmission line

Description : Transmission lines when connected to antenna have A. capacitive load B. resistive load whose resistance is less than characteristics impedance C. resistive load at the resonant frequency D. resistive load whose resistance is greater than the characteristic impedance of the line

Last Answer : C. resistive load at the resonant frequency

Description : Load regulation is a measure of a power supplies ability keep a constant output under conditions of changing A) Line voltage B) Current demand C) Temperature D) Oscillator frequency.

Last Answer : A) Line voltage

Description : Two alternators rated are 200 KW at 4% regulation, 400 KW 5% regulation operating in parallel at 50HZ , when supply 600 KW the new frequency is a) 50 b) 49 c) 51.3 d) 47.7

Last Answer : Ans: 47.7

Description : Which of the following statements regarding cytokines is incorrect? A. Cytokines act directly on target cells and may potentiate the actions of one another. B. Interleukin 1 (IL-1) ... organ dysfunction syndrome because of its multiple actions and the secondary cascades that it stimulates.

Last Answer : Answer: C DISCUSSION: Cytokines are soluble peptide molecules that are synthesized and secreted by a number of cell types in response to injury, inflammation, and infection. Cytokines, which ... is thought to play a central role in the stress response, particularly in response to endotoxemia

Description : The main limitation for power handling capability of short length transmission lines and cables is (A) power factor (B) stability (C) thermal effect limit (D) conductor size

Last Answer : The main limitation for power handling capability of short length transmission lines and cables is thermal effect limit

Description : What is short transmission line?

Last Answer : Length is about 50 km. Voltage level is up to 20 kV Capacitance effect is negligible Only resistance and inductance are taken in calculation.

Description : The true power indicated by a wattmeter depends on the current flow through the load, the magnitude of the potential across the load, and the _____________. A. power factor of the load B. angle of coil displacement C. inertia of the movable coil D. high resistance from the load

Last Answer : Answer: A

Description : The true power indicated by the pointer movement of a wattmeter depends on the current flow through the load, the magnitude of the potential across the load, and the ____________. A. power factor of the ... B. angle of coil displacement C. inertia of the movable coil D. high resistance from the load

Last Answer : Answer: A

Description : The size of a conductor used in power cables depends on the (A) operating voltage. (B) power factor. (C) current to be carried. (D) type of insulation used.

Last Answer : (C) current to be carried.

Description : Autotransformer starters or compensators are sometimes used with polyphase induction motors to _____________. A. reduce the voltage applied to the motor during the starting period B. increase the voltage for ' ... to be either stepped up or down, depending on the application, to ensure full torque

Last Answer : Answer: A

Description : When is the Ferranti effect on long over head lines experienced? a) The lines are lightly loaded b) The lines are heavily loaded c) The lines are fully loaded d) The power factor is unity

Last Answer : Ans: A

Description : What is meant by antenna gain? A. The final amplifier gain minus the transmission line losses (including any phasing lines present) B. The ratio of the amount of power produced by the antenna ... D. The numeric ratio relating the radiated signal strength of an antenna to that of another antenna

Last Answer : D. The numeric ratio relating the radiated signal strength of an antenna to that of another antenna

Description : Computers cannot communicate with each other directly over telephone lines because they usedigitalpulses whereas telephone lines useanalog sound frequencies. What is the name of the device which permits digital to analog ... A. Interface B. Modem C. Attenuation D. Teleprocessor E. None of the above

Last Answer : Modem

Description : In the analysis of which of the following lines shunt capacitance is neglected ? (a) Short transmission lines (b) Medium transmission lines (c) Long transmission lines (d) Medium as well as long transmission lines

Last Answer : (a) Short transmission lines

Description : The leakage current in the transmission lines is referred to as the a) Resistance b) Radiation c) Conductance d) Polarisation

Last Answer : Ans: C

Description : What are the different relays that employed for protection of apparatus and transmission lines?

Last Answer : Answer: The relays that are usually employed for protection of transmission lines include • Over current relay • Directional relay • Distance relay • Under Voltage relay • Under-frequency relay • Thermal relay • Differential relay • Phase sequence relays • pilot relays

Description : Why Earth Wire is provided in the overhead transmission lines?

Last Answer : Earth wire is provided above the overhead transmission lines for protection against lightning strokes. The ground wire or earth wire protects the phase conductors or line conductors by attracting itself the ... traveling waves set in the lines by acting a short circuit secondary of the line current

Description : Why, when birds sit on transmission lines or current wires doesn't get shock?

Last Answer : It's true that if birds touch the single one line (phase or neutral) they don't get electrical shock... if birds touch 2 lines than the circuit is closed and they get electrical shock. so ... is grounded..So that means that human who touch the line closes the circuit between phase and neutral.

Description : Why, when birds sit on transmission lines or current wires doesn't get shock?

Last Answer : A:Its true that if birds touch the single one line (phase or neutral) they don't get electrical shock... if birds touch 2 lines than the circuit is closed and they get electrical shock.. so if a human ... the air. If he is standing on the ground then touching the line (phase) he will get a shock.

Description : ACSR (Aluminium Conductor Steel Reinforced) are used as (A) over head transmission lines. (B) super conductors. (C) fuse (D) underground cables.

Last Answer : (A) over head transmission lines.

Description : Define the followings.   Insulation level, Rated short circuit breaking current, Making current, Short time rating, Impulse withstand voltage, Power frequency withstand voltage .

Last Answer : Insulation level - it is the combination of rated voltage, the corresponding impulse withstand voltage, which together characterize the insulation of the equipment as regards its ability to withstand ... wave of power frequency (50 Hz) which the insulation of equipment should withstand. 

Description : The absorption ofradiowaves bythe atmosphere depends on a. their frequency b. their distance from the transmitter c. the polarization of the waves d. the polarization of the atmosphere

Last Answer : a. their frequency

Description : According to Coast Guard Regulation (46 CFR) for emergency power and lighting systems, which of the listed items is the only permissible starting aid for the emergency diesel generator engine? A. Ether B. Lube oil heater C. Jacket water heater D. Fuel oil heater

Last Answer : Answer: C

Description : Define the percentage voltage regulation and efficiency of a power transformer.  

Last Answer : Voltage regulation is the difference between no load voltage and full load voltage by no load voltage. Voltage regulation = No load voltage - Full load voltage / No load voltage. Voltage regulation is mentioned ... . % Efficiency = Output in watts * 100 / Output in watts + losses. 

Description : The velocity factor in transmission lines vary from ___ to ___. A. 0.6 to 0.8 B. 0.3 to 0.5 C.0.5 to 0.9 D. 0.8 to 0.9

Last Answer : C.0.5 to 0.9

Description : Cell regulation can be thought of as the effector side of cell communication. Most commonly cell regulation occurs by means of extracellular chemical messengers. Which of the following statement(s ... d. Most hormones, local mediators, and neurotransmitters readily cross the cell plasma membrane

Last Answer : Answer: b, c Depending on how the extracellular messenger arrives, cell regulation can be classified as paracrine, endocrine, or neurocrine. In paracrine regulation, a chemical messenger ... , local mediators, and neurotransmitters are water-soluble and cannot readily cross the plasma membrane

Description : 51 A transformer has negative voltage regulation when its load power factor is A. Zero B. Unity C. Leading D. Lagging

Last Answer : C. leading

Description : A transformer has negative voltage regulation when its load power factor is   (1) Zero (2) Unity (3) Leading (4) Lagging

Last Answer : 0

Description : Minimum voltage regulation occurs when the power factor of the load is?

Last Answer : Minimum voltage regulation occurs when the power factor of the load is leading.

Description : In an alternating current electrical system, a low system power factor is a direct sign of _____________. A. wasted energy B. efficient operation C. a short in the exciter field windings D. an excessive number of minor system grounds

Last Answer : Answer: A

Description : At dead short circuit at terminals of Alternator then the current I is a) ZPF Lag b) ZPF lead c) Unity power factor d) 0.8 Power factor lag

Last Answer : Ans: ZPF Lag

Description : Stopping distance of vehicles : When brakes are applied to a moving vehicle, the distance it travels before stopping is called stopping distance. It is an important factor for road safety and depends on ... the brake with the deceleration of 5m/s2. Find the stopping distance of the car -Science

Last Answer : Here u=72 km/hr = 72×10003600m/s=2072×10003600m/s=20 m/s , v=0 a= -5 m/s2 Now using the relation v2=u2+2asv2=u2+2as 0=(20)2+2×(−5)×s0=(20)2+2×(−5)×s s=40ms=40m

Description : As shown in the illustration, the function of the switch labeled 'PFSW' is to determine the ______________. EL-0003 A. bus frequency B. reactive volt amperes of the bus C. frequency of either generator D. power factor of either generator

Last Answer : Answer: D

Description : In order to increase its range of measurement, a resistance would be placed in series with which of the following instruments? A. DC voltmeter B. DC ammeter C. frequency meter D. power factor meter

Last Answer : Answer: A

Description : With increase in temperature, the rate constant obeying Arrhenius equation (A) Increases (B) Decreases (C) Decreases exponentially (D) Can either increase or decrease; depends on the frequency factor

Last Answer : (C) Decreases exponentially

Description : It is an average power of a radio transmitter supplied to the antenna transmission line taken during a long sufficient interval of time and compared with the lowest frequency encountered in the modulation ... operating conditions. A. Carrier power B. Rated power C. Mean power D. Peak envelop power

Last Answer : C. Mean power

Description : Referred to as an average power from the radio transmitter supplied to the antenna transmission line taken during one radio frequency cycle under no modulation. A. Carrier power B. Rated power C. Peak envelop power D. Mean power

Last Answer : A. Carrier power

Description : Average power of a radio transmitter supplied to the antenna transmission line by a transmitter during one radio frequency cycle taken under the condition of no modulation. A. Peak envelop power B. Rated power C. Carrier power D. Mean power

Last Answer : C. Carrier power