Can you help by answering this question?

Which of the following is not equivalent to watts?

147 views
in Electric Power Transmission by
A 50 Hz, 4 pole turboalternator rated at 20 MVA. 13.2 KV has an inertia constant H = 4 KW sec/KVA. The K.E. stored in the rotor at synchronous speed is

1 Answer

0 votes
by

A 50 Hz, 4 pole turboalternator rated at 20 MVA. 13.2 KV has an inertia constant H = 4 KW sec/KVA. The K.E. stored in the rotor at synchronous speed is 80 MJ

Related questions

1 answer 118 views

A 60 Hz, 4 pole turbo generator rated 100 MVA, 13.8 KV has an inertia constant of 10 MJ/MVA. Find the stored energy in the rotor at synchronous speed.  (A) 10 MJ (B) 100 J (C) 1000 J (D) 1000 MJ 

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
1 answer 46 views

A 100 MVA, 11 KV, 3-phase, 50 Hz, 8—pole synchronous generator has an inertia constant H equal to 4 seconds. The stored energy in the rotor of the generator at synchronous speed will be  A) 100 MJ B) 400 MJ C) 800 MJ D) 12.5 MJ

asked May 20, 2018 in Synchronous machine by Shimroz123
1 answer 42 views

A 50 Hz, 4-pole, 500 MVA, 22 kV turbo-generator is delivering rated megavolt amperes at 0.8 power factor. Suddenly a fault occurs reducing in electric power output by 40%. Neglect losses and assume constant power input to the shaft. The accelerating torque in the generator in MNm at the time of fault will be  (A) 1.528 (B) 1.018 (C) 0.848 (D) 0.509

asked May 25, 2018 in Power system by Shimroz123
1 answer 80 views

The locked rotor current in a 3-phase, star connected 15 , kW 4 , pole 230 V , 50 Hz induction motor at rated conditions is 50 A. Neglecting losses and magnetizing current, the approximate locked rotor line current drawn when the motor is connected to a 236 , V 57 Hz supply is  (A) 58.5 A (B) 45.0 A (C) 42.7 A (D) 55.6 A

asked May 17, 2018 in Electrical Machine by Shimroz123
0 answers 108 views

A single phase transformer rated at 3000 kVA, 69 kV 4.16 kV, 60 Hz has a total internal impedance Zp of 127 ohm, referred to the primary side. Calculate the primary current if the secondary is accidentally short circuited.  (A) 43.5 A (B) 543 A (C) 9006 A (D) 721 A 

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
1 answer 63 views

The inertia constant of a 100 MVA, 11 kV water wheel generator is 4. The energy stored in the rotor at the synchronous speed is: A) 400 Mega Joule B) 400 Kilo Joule C) 25 Mega Joule D) 25 Kilo Joule

asked Jun 4, 2018 in Power system by Shimroz123
1 answer 29 views

A 3 phase, 400 volts, 50 Hz, 100 kW, 4 pole squirrel cage induction motor with a rated slip of 2% will have a rotor speed of: (A) 1500 rpm (B) 1470 rpm (C) 1530 rpm (D) 1570 rpm

asked Apr 11, 2018 in Computer Engineering by Shimroz123
1 answer 62 views

If the inertia constant H of a machine of 200 MVA is 2 p.u., its value corresponding to 400 MVA will be   (a) 4 p.u. (b) 2 p.u. (c) 1.0 p.u. (d) 0.5 p.u. 

asked May 13, 2018 in Electrical Engineering by Shimroz123
1 answer 16 views

A 400 V, 15 kW, 4-pole, 50 Hz, Y-connected induction motor has full load slip of 4%. The output torque of the machine at full load is  (A) 1.66 Nm (B) 95.50 Nm (C) 99.47 Nm (D) 624.73 Nm

asked May 17, 2018 in Induction Machine by Shimroz123
0 answers 188 views

A 30 MVA, 13.2 KV synchronous generator has a solidly grounded neutral. Its positive, negative and zero sequence impedances are 0.30, 0.40 and 0.05 pu respectively. What value of reactance must be placed in the generator neutral so that the fault current for a line to ground fault of zero fault impedance shall not exceed the rated line current.  (A) 4.416 ohm (B) 8.8 ohm (C) 2.08 ohm (D) 10.2 ohm 

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
1 answer 25 views

A generator is connected through a 20 MVA, 13.8/138 kV step down transformer, to a transmission line. At the receiving end of the line a load is supplied through a step down transformer of 10 MVA, 138/69 kV rating. A 0.72 pu. load, evaluated on load side transformer ratings as base values , is supplied from the above system. For system base values of 10 MVA and 69 kV in load circuit, the value of the load (in per unit) in generator will be (A) 36 (B) 1.44 (C) 0.72 (D) 0.18

asked May 25, 2018 in Power system by Shimroz123
1 answer 21 views

The stator of a 415V, 50 Hz, 4-pole slip ring Induction Motor is excited by rated frequency with slip rings open circuited. The rotor is made to rotate at a speed of 600 rpm in the opposite direction to the normal direction, The frequency of induced voltage across slip ring is A) 30 Hz B) 70 Hz C) 20 Hz D) 35 Hz

asked Jun 17, 2018 in Induction Machine by Shimroz123
1 answer 137 views

A 3-phase, 11 kv, 50 Hz, 200 kW load has a power factor of 0.8 lag. A delta connected 3-phase capacitor is used to improve the power factor to unity. The capacitance perphase of the capacitor in micro-farads is?

asked Mar 27, 2018 in Power system by Shimroz123
0 answers 23 views

The constant of a given energy meter is 500 revolution/kWh. At the test 4.4 kW full load, meter completes 50 revolutions in 86 seconds. The percentage error of the meter is (a) –4.86% (b) 4.86% (c) 2.0% (d) 3.0%

asked May 26, 2018 in Electrical Measurements and Instrumentation by Shimroz123
0 answers 15 views

A 3-phase, 2 pole, 11 kV, 10000 kVA alternator has earthed neutral through a resistance of 7.0Ω. The machine has current balance protection which operates if out of balance current exceeds 20% of full load. Determine %age of winding protected against earth fault (1) 10.6% (2) 11.6% (3) 10.9% (4) 11.2% 

asked Apr 11, 2018 in Electrical Engineering by Shimroz123
1 answer 33 views

A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The net Voltage across armature resistance at the time of plugging will be

asked May 8, 2018 in Electrical Machine by Shimroz123
1 answer 15 views

The p.u. parameter for a 500 MVA machine on its own base are: inertia, M = 20 p.u. ; reactance, X = 2 p.u. The p.u. values of inertia and reactance on 100 MVA common base, respectively, are (A) 4, 0.4 (B) 100, 10 (C) 4, 10 (D) 100, 0.4

asked May 25, 2018 in Power system by Shimroz123
0 answers 19 views

A 10 kW electric motor drives a vehicle at an average speed of 50 Km/h. Ten, 12 V, 100A-h batteries supply the motor, the maximum distance that the vehicle may travel before the batteries must be recharged, will be : (A) 30 Km (B) 45 Km (C) 60 Km (D) 80 Km

asked Mar 31, 2018 in Electrical Engineering by Shimroz123
1 answer 14 views

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

asked May 17, 2018 in Induction Machine by Shimroz123
0 answers 25 views

A Transformer rated 250 kVA, 4160 V / 480 V, 60 Hz has an impedance of 5.1%. Calculate the total impedance of the transformer referred to the primary side.  (A) 69 ohm (B) 0.92 ohm (C) 3.52 ohm (D) 0.51 ohm

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
0 answers 24 views

A d.c. ampere-hour meter is rated at 5A, 250 V. The declared constant is 5 A sec/revolution. The constant in revolution/kwh will be (a) 2880 (b) 2680 (c) 2480 (d) 2280

asked May 25, 2018 in Electrical Measurements and Instrumentation by Shimroz123
0 answers 14 views

One 200 KVA transformer has an iron loss of 1 KW and full load Cu loss of 2 KW. Its load KVA corresponding to maximum efficiency is:  (A) 100 KVA (B) 141.4 KVA (C) 50 KVA (D) 200 KVA 

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
0 answers 76 views

A 3-phase circuit breaker is rated at 1250 A, 2000 MVA, 33 kV, 4s. Its making current capacity will be   (a) 35 kA (b) 89 kA (c) 79 kA (d) 69 kA

asked Apr 10, 2018 in Electrical Engineering by Shimroz123
0 answers 241 views

A three phase breaker is rated at 2000 MVA, 33 kV, its making current is  (A) 70 kA (B) 89 kA (C) 49 kA (D) 35 kA 

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
1 answer 83 views

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

asked May 3, 2018 in Electric Power Transmission by Shimroz123
1 answer 18 views

If a transformer is switched on to a voltage more than the rated voltage?

asked Mar 19, 2018 in Transformer by Shimroz123
1 answer 17 views

A single-phase, 50 kVA, 250 V/500 V two winding transformer has an efficiency of 95% at full load, unity power factor. If it is re-configured as a 500 V/750 V auto-transformer, its efficiency at its new rated load at unity power factor will be  (A) 95.752% (B) 97.851% (C) 98.276% (D) 99.241%

asked May 17, 2018 in Transformer by Shimroz123
1 answer 28 views

The maximum constant load torque under which a synchronous motor will pull into synchronism at rated rotor supply voltage and frequency is known as?

asked Mar 20, 2018 in Synchronous machine by Shimroz123
1 answer 145 views

what will happen when excitation of an unloaded salient pole synchronous motor suddenly gets disconnected?

asked Mar 18, 2018 in Synchronous machine by Shimroz123
0 answers 67 views

The magnetizing reactance of a 4 kV/ 400 V, 50 Hz single-phase transformer on low voltage side is 35 Ω. The magnetizing reactance on the high voltage side is (A) 0.35 Ω (B) 3.5 Ω (C) 350 Ω (D) 3500 Ω

asked Jun 4, 2018 in Single phase transformer by Shimroz123
1 answer 62 views

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

asked Apr 25, 2018 in Electrical Engineering by Shimroz123
1 answer 17 views

A 50 kW dc shunt is loaded to draw rated armature current at any given speed. When driven  (i) at half the rated speed by armature voltage control and (ii) at 1.5 times the rated speed by field control, the respective output powers delivered by the motor are approximately. (A) 25 kW in (i) and 75 kW in (ii) (B) 25 kW in (i) and 50 kW in (ii) (C) 50 kW in (i) and 75 kW in (ii) (D) 50 kW in (i) and 50 kW in (ii)

asked May 17, 2018 in DC machine by Shimroz123
1 answer 114 views

A 500 MVA, 11 KV synchronous generator has 0.2 p.u. synchronous reactance. The p.u. synchronous reactance on the base values of 100 MVA and 22 KV is  A) 0.16 B) 0.01 C) 4.0 D) 0.25

asked May 17, 2018 in Synchronous machine by Shimroz123
0 answers 28 views

A system function has a pole at s=0 and a zero at s= -1. The constant multiplier is unity. For an excitation cos(t), What is the steady-state response?  (A) √2sin(t+450) (B) √2sin(t-450) (C) sin(t-450) (D) Sin(t) 

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
1 answer 18 views

Capacitors for power factor correction are rated in?

asked Mar 25, 2018 in Electrical Engineering by Shimroz123
0 answers 9 views

A SCR has an anode supply of sine voltage 200V rms, 50 Hz applied through a 100Q resistor and fired at an angle of 60°. Assuming no voltage drop, the rms value of the output voltage is : (A) 89,7 V (B) 126.7 V (C) 166.7 V (D) 288.28 V

asked Apr 14, 2018 in Electrical Engineering by Shimroz123
1 answer 28 views

A separately excited d.c. machine is coupled to a 50 Hz, three-phase, 4-pole induction machine as shown in the figure. The Dc machine is energized first and the machines rotate at 1 600 1pm. Subsequently the induction machine is also connected to a 50 Hz, three phase source, the phase sequence being consistent with the direction of rotation. In steady state

asked May 20, 2018 in DC machine by Shimroz123
1 answer 34 views

A balanced three-phase, 50 Hz voltage is applied to a 3 phase, 4 pole, induction motor. When the motor is delivering rated output, the slip is found to be 0.05. The speed of the rotor m.m.f. relative to the rotor structure is: (A) 1500 r.p.m. (B) 1425 r.p.m. (C) 25 r.p.m. (D) 75 r.p.m

asked Apr 11, 2018 in Electrical Engineering by Shimroz123
0 answers 42 views

If 5000 kW power is transmitted at 220 kV in place of 11 kV, reduction in the value of electric current will be (a) 90% (b) 95% (c) 5% (d) 10% 

asked May 26, 2018 in Electric Power Transmission by Shimroz123
1 answer 35 views

The corona loss in a 50 Hz system is 0.25 kW/ph/km. At a frequency of 60 Hz, the corona loss would be   (a) 0.30 kW/ph/km (b) 0.36 kW/ph/km (c) 028 kW/ph/km (d) 0.21 kW/ph/km

asked May 13, 2018 in Power system by Shimroz123
1 answer 52 views

The corona loss on a particular system at 50 Hz is 1 kw/phase per km. The corona loss on the same system with supply frequency 25 Hz will be?

asked Mar 27, 2018 in Power system by Shimroz123
1 answer 28 views

The armature current on symmetrical 3 phase short circuit of a synchronous machine (salient pole)  (A) has q -axis current only (B) has d -axis current only (C) has both d and q axis currents (D) cannot be divided between q and d axis currents

asked Apr 29, 2018 in Electrical Machine by Shimroz123

Welcome to electronics2electrical.com here you can ask questions related to electrical, electronics, mechanical, telecommunication, instrumentation, computer, mathematics, physics etc.
Be respectful to all the members. Do not copy and paste the answers from other websites which have copyright content. While asking question give full details about it.

Categories

Most popular tags

power motor dc circuit transformer voltage current used system phase resistance factor synchronous load ac energy induction electric generator series frequency between speed capacitor use electrical meter line difference control type mosfet transmission magnetic plant high single instrument bjt unit source advantages function diode and machine winding field define torque parallel amplifier supply shunt thyristor motors electricity arduino maximum time relay armature problem value on transformers types coil diagram state flow ratio material three formula starting direction theorem method emf operating efficiency digital wave microprocessor test instruments inductance loss measure operation connected signal low applications effect single-phase network temperature working constant losses different law wattmeter measuring compare controlled breaker drive device logic rc full switch flux wire resistivity disadvantages free of materials machines angle force converter conductor transistor gain open protection scr core measurement number bridge principle generators reactance circuits negative the friction iron loop short pole battery conservation steam resistors hysteresis computer using analog lines secondary station gate a rectifier inverter linear induced relays nuclear capacitance basic characteristics design direct work rotor electronics ammeter forces diesel damping rlc connection factors capacitors minimum insulation moving regulation running self systems air fault range main stability quality starter igbt eddy alternator ideal rl average 3-phase plants arc thermal error fuzzy biasing dielectric pressure balanced superposition errors copper rotation feedback impedance measured electronic electrons charge inductive transfer explain start off back curve over solar is three-phase tariff locomotive peak bias zener engineering commutator surge conductors rating universal potentiometer density permanent mechanical transducer capacity memory adc excitation two fuse pure harmonics application semiconductor inductor internal pmmc reaction welding resonance traction permeability breakers rms designed electromagnetic si generation brushes switching capacitive shaded rate 1 distribution resistor methods delta star oscillator reluctance simplification algebra 8085 boolean weston dynamometer insulating strength installation definition fuel heating earth units
...