In a 3 phase, 4 wire unbalanced System, the current in the neutral wire is 18 A. The magnitude of the zero sequence current is 6 A
Description : In a 3-phase 4-wire distribution system three unbalanced but equal magnitude impedances are connected between respective lines and neutral. The magnitude of current in the neutral conductor for RYB and RBY phase sequences ... ) zero (B) same (C) different (D) same in magnitude but differs in phase.
Last Answer : In a 3-phase 4-wire distribution system three unbalanced but equal magnitude impedances are connected between respective lines and neutral. The magnitude of current in the neutral conductor for RYB and RBY phase sequences are different
Description : The minimum number of wattmeter(s) required to measure 3-phase, 3-wire balanced or unbalanced power is A) 1 B) 2 C) 3 D) 4
Last Answer : B
Description : 4. A three-phase, four-wire system having \( 250 V \) line-to-neutral has the following loads connected between the respective lines and the neutral. Calculate the current in the neutral wire?\[Z_{R}=20 \angle 0^{\circ} ... Z_{Y}=20 \angle 35^{\circ} \Omega, Z_{B}=20 \angle-55^{\circ} \Omega\](10M)
Last Answer : 4. A three-phase, four-wire system having \( 250 V \) line-to-neutral has the following loads connected ... =20 \angle-55^{\circ} \Omega \] (10M)
Description : What happens when a neutral wire touches a phase wire ?
Last Answer : Maximum current flow due to Short circuit, limited value of fuse will burn else apparatus and conductor will be damaged.
Description : During vibrations any machine has unbalanced force of 392N and if it transmitted force of magnitude 58.3N then transmissibility value is A 0.481 B 0.822 C 0.148 D 0.296
Last Answer : C 0.148
Description : Define balanced and unbalanced load in three phase circuit.
Last Answer : Balanced Load: When all the imedances of 3 phases are equal in magnitude and of same nature then load is said to be balanced. Unbalanced Load: When all the imedances of 3 phases are not equal in magnitude and of different nature then load is said to be unbalanced.
Description : An electric bulb is connected on a holder. One end of the wire is connected to the phase and the remaining one connected to earth instead of neutral. The bulb will glow or not? If yes then what is the need of neutral?
Last Answer : 1. Yes the bulb will be glow & neutral is return path of Circuit it is originated from distribution transformers star point, form this point only neutral is taken. 2. Then what is the need ... : It gives assurance of reliable centralized earthling as your home may or may not have reliable earthling.
Description : What type of balun (balanced-to-unbalanced) is used in high frequency applications? A. Transformer type balun B. A specially configured coaxial transmission line C. A specially configured parallel-wire line D. A λ/2 transformer balun
Last Answer : B. A specially configured coaxial transmission line
Description : A transmission line consisting of two conductors that have equal resistance per unit length. A. Unbalanced line B. Open-wire line C. Balanced line D. Coaxial line
Last Answer : C. Balanced line
Description : In a three-phase system, when the loads are perfectly balanced, the value of neutral current is equal to: A. Zero B. One-third of the maximum value C. Two -third of the maximum value D. The maximum value
Last Answer : In a three-phase system, when the loads are perfectly balanced, the value of neutral current is equal to: Zero
Description : A wire of length `L metre ` , carrying a current `I `ampere is bent in the form of a circle . The magnitude of its magnetic moment is …………. ` MKS unit
Last Answer : A wire of length `L metre ` , carrying a current `I `ampere is bent in the form of a circle . The magnitude of ... `(L^(2)I)/(4pi)` D. `(LI)/(4pi)`
Description : Current `i` is carried in a wire of length `L`. If the wire is turned into a circular coil, the maximum magnitude of torque in a given magnetic field
Last Answer : Current `i` is carried in a wire of length `L`. If the wire is turned into a circular coil, the maximum magnitude ... iB)/(4pi)` D. `(L^(2)B)/(4pi)`
Description : For a straight wire, induced current depends uponA. the speed of movement of wire B. the length of wire C. the magnitude of magnetic flux density D. all of above
Last Answer : all of above
Description : The shape of a magnetic field around a long straight current carrying wire is: w) elliptical. x) square y) varies depending on the magnitude of the current z) circular
Last Answer : ANSWER: Z -- CIRCULAR
Description : Find the magnitude of the displacement current density in air at a frequency of 18GHz in frequency domain. Take electric field E as 4 units. a) 18 b) 72 c) 36 d) 4
Last Answer : d) 4
Description : A wire carrying current is – (1) positively charged (2) negatively charged (3) neutral (4) charged with a type depending upon current strength
Last Answer : (3) neutral
Description : All electrical appliances are connected in parallel to each other between the main line and neutral wire to get a. same current b. same current and potential difference c. different current but same potential difference d. different current and potential differences
Last Answer : c. different current but same potential difference
Description : A wire carrying current is (1) positively charged (2) negatively charged (3) neutral (4) charged with a type depending upon current strength
Last Answer : neutral
Description : The maximum magnitude of shear stress due to shear force F on a rectangular section of area A at the neutral axis, is (A) F/A (B) F/2A (C) 3F/2A (D) 2F/3A
Last Answer : (C) 3F/2A
Description : Why should switch be connected only on the live wire and never on the neutral wire?
Last Answer : Current runs from the transformer, through the protective device, through the load and back through the protective device (if on RCD). If the protective device is only a CB the current passes ... the circuit will operate correctly but this is an unsafe practice and does not meet the standards.
Description : A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50 Hz source, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor is (A) 100 (B) 98 (C) 52 (D) 48
Last Answer : A 4-pole induction motor, supplied by a slightly unbalanced three-phase 50 Hz source, is rotating at 1440 rpm. The electrical frequency in Hz of the induced negative sequence current in the rotor is 98
Description : Four wires of the same material and dimensions as under are stretched by a load of same magnitude separately. Which of them will be elongated maximum? (a) wire of 3m length and 1.5 mm diameter (b) ... and 2mm diameter (c) wire of 2m length and 2mm diameter (d) wire of 1m length and 1mm diameter
Last Answer : Ans:(a)
Description : E.M.F for a coil depends upon A. the cross sectional area B. no. of turns of wire C. the magnitude of magnetic flux density D. all of above
Description : In a three-wire, 230/115 volt DC system, the potential between neutral and negative is _____________. A. 0 volts B. 115 volts C. 230 volts D. 460 volts
Last Answer : Answer: B
Description : What are the reasons for unbalanced current in motor?
Last Answer : a. Loose power cable connection. b. Voltage unbalance. c. Short-circuited turns of coils of winding.
Description : In a three-phase supply floating neutral is undesirable because it way give rise to?
Last Answer : In a three-phase supply floating neutral is undesirable because it way give rise to unequal line voltages across the load.
Last Answer : Due to no potential difference between the ends of the circiut there is no existance of current
Description : The transformer which transforms unbalanced line to a balanced line is better known as (A) Impedance transformer (B) Amplifier (C) Balun (D) Oscillator
Last Answer : The transformer which transforms unbalanced line to a balanced line is better known as Balun
Description : In load flow studies of a power system, a voltage control bus is specified by a) Real power and reactive power b) Reactive power and voltage magnitude c) Voltage and voltage phase angle d) Real power and voltage magnitude
Last Answer : d) Real power and voltage magnitude
Description : In a three phase half wave rectifier feeding resistive load, if the input source is a three phase 4 wire system and line to line voltage is 100 V. The supply frequency is 400 Hz. The ripple frequency at the output is: (1) 400 Hz (2) 800 Hz (3) 1200 Hz (4) None of these
Last Answer : In a three phase half wave rectifier feeding resistive load, if the input source is a three phase 4 wire system and line to line voltage is 100 V. The supply frequency is 400 Hz. The ripple frequency at the output is: 1200 Hz
Description : A 3 phase 4 wire system is commonly used for: - a) Primary distribution b) Secondary distribution c) Primary transmission d) Secondary transmission
Last Answer : A 3 phase 4 wire system is commonly used for: - Secondary distribution
Description : Magnitude of current at resonance in R-L-C circuit?
Last Answer : The current will be maximum if it is a series rlc circuit.
Description : What can I do about a wall switch for an overhead light if the socket doesn't have a neutral wire and the switch does?
Last Answer : answer:This doesn't make sense. The ground wire is the bare-naked copper wire that's a little thinner than the others. In addition to a ground wire, if any, there must be two regular insulated wires ... though they can be wired to switch neutral. For lights it shouldn't matter. Does any of this fit?
Description : What is the color of live and neutral wire ?
Last Answer : The color of the live wire is red and the color of the neutral wire is black.
Description : What is the voltage of a neutral wire ?
Last Answer : Neutral cable voltage 0
Description : How to find a neutral wire on a device?
Last Answer : It all depends on from which country you are from. From seeing the wiring color code, I assume that you are probably from an asian country or a country that follows IEC 60446 standards. As you have red ... So it must be ground or earth. So the third one ie: black color wire should be the neutral.
Description : In an electrical circuit, a fuse is connected (a) in the live wire (b) in the neutral wire (c) in the earth wire (d) anywhere—it makes no difference
Description : When the main switch of the house is put off it disconnects the – (1) live wire only (2) live wire and the earth wire (3) live wire and the neutral wire (4) earth wire and the neutral wire
Last Answer : (3) live wire and the neutral wire Explanation: Three wires enter most homes from the power pole-two "hot" wires and a third "neutral" wire. Each hot wire provides 120- volt current for ... the main switch is put off because the electric circuit (the path where the electricity travels) gets opened.
Description : The wire having a green plastic covering is a _______. (1) Line wire (2) Neutral wire (3) Earth wire (4) None of these
Last Answer : (3) Earth wire Explanation: The earth wire is a crucial part of the home electrical system and is designed to protect against electric shock.
Description : When the main switch of the house is put off it disconnects the (1) live wire only (2) live wire and the earth wire (3) live wire and the neutral wire (4) earth wire and the neutral wire
Last Answer : live wire and the neutral wire
Description : Which color wire is neutral?
Last Answer : Black but I think it depends with the place.
Description : In polar vector quantization r is called ________. a. Quantum b. Phase c. Magnitude d. None of above
Last Answer : c. Magnitude
Description : 6 In a two winding transformer, the primary and secondary induced emf E1 & E2 are always A. equal in magnitude B. anti phase with each other C. in phase with each other D. determined by load on transformer secondary
Last Answer : C. In phase with each other
Description : In a certain three -wire Y -connected generator, the phase voltages are 2 kV. The magnitudes of the line voltages will be: A. 2,000 V B. 6,000 V C. 666 V D. 3,464 V
Last Answer : In a certain three -wire Y -connected generator, the phase voltages are 2 kV. The magnitudes of the line voltages will be: 3,464 V
Description : Ungrounded neutral transmission system is not recommended because of system (a) insulation being overstressed due to over voltages (b) insulation overstress may lead to failure and subsequent phase to phase faults (c) being inadequately protected against ground fault (d) all of the above
Last Answer : (d) all of the above
Description : A singly reinforced concrete beam of 25 cm width and 70 cm effective depth is provided with 18.75 cm2 steel. If the modular ratio (m) is 15, the depth of the neutral axis, is (A) 20 cm (B) 25 cm (C) 30 cm (D) 35 cm
Last Answer : Answer: Option C
Description : The effective depth of a singly reinforced rectangular beam is 300mm. the section is over-reinforced and the neutral axis is 120mm below the top. If the maximum stress attained by concrete is 5N/mn2 and the modular ratio ... in the steel will (a) 130N/mm2 (b) 135N/mm2 (c) 160N/mm2 (d) 180N/mm2
Last Answer : (b) 135N/mm2
Description : What Are The Causes Of Vibration? a. Unbalanced centrifugal forces in the system. b. Elastic nature of the system. c. Winds may cause vibrations of certain systems such as electricity lines, telephones lines etc. d. All of the above
Last Answer : d. All of the above