102 views

**Description :** Express the following functions in cosine form

**Last Answer :** Express the following functions in cosine form

116 views

**Description :** Evaluate the following quantities and express your results in polar form

**Last Answer :** Evaluate the following quantities and express your results in polar form

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**Description :** Calculate these complex numbers and express your results in rectangular form

**Last Answer :** Calculate these complex numbers and express your results in rectangular form

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**Description :** How many volts does it take to power an Arduino?

**Last Answer :** 5volts is enough to supply the Arduino.

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**Description :** I need a new 12 volt AC adapter; do amps matter?

**Last Answer :** answer:Amperage does matter. if you do not use the proper amperage for a certain device, it will either fry again or not work at all. i had this problem with an extended volume control on a ... they also have the best selection of AC adapters i have ever seen. they were very helpful at RS.

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**Description :** Can I plug a 6V adapter into a USB-hub?

**Last Answer :** Try it for 15 mins, feel it, and if it scalds your hand like you just touched the sun, then its probably not a good idea to keep using this.

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**Description :** How many amps run through a high tension power line?

**Last Answer :** Watts/Volts = Amps. So a typical 400 kV (400,000 V) might have a current draw of 100 MW (100,000,000 W). This would equal 250 Amps.

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**Description :** The short wavelength limit of the X-rays produced, through the complete coversion' of the energy of a beam of electrons, accelerated through a potential, V, is 0.4125 Å. Taking h = 6.6 x 10-34 J-s. The value of V, and the ... 7 Å (2) 30 kV and 0.07 Å (3) 3 kV and 0.007 nm (4) 3 kV and 0.7 nm

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**Description :** How many volts is 13.8 kV?

**Last Answer :** 13,800 volts1 kv = 1 kilovolt = 1000 volts

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**Description :** How many volts is 13.8 kV?

**Last Answer :** 13,800 volts1 kv = 1 kilovolt = 1000 volts

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**Description :** The dielectric strength of a vacuum or dry air is approximately ________________. A. 450 volts/inch B. 1000 volts/inch C. 20-kv/inch D. 50-kv/inch

**Last Answer :** Answer: C

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**Description :** Express the following in more simple terms. (a) 250,000 volts, (b) 25,000,000 microvolts, (c) 0.001 millivolt.

**Last Answer :** (a) 250 kV, (b) 25 V, (c) 1µV

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What unit is used to express the number of amps and volts needed by a particular device to function?

**Description :** What unit is used to express the number of amps and volts needed by a particular device to function?

**Last Answer :** Feel Free to Answer

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**Description :** Transmission voltage of ll kV is normally used for distances upto (a) 20—25 km (b) 40—50 km (c) 60—70 km (d) 80—100 km

**Last Answer :** (a) 20—25 km

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**Description :** The voltage at the two ends of a transmission line are 132 KV and its reactance is 40 ohm. The Capacity of the line is (A) 435.6 MW (B) 217.8 MW (C) 251.5 MW (D) 500 MW

**Last Answer :** (A) 435.6 MW

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**Description :** 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

**Last Answer :** 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: 435.6 MW

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**Description :** A common-emitter circuit has an input voltage of 0.1 volt, an output voltage of 2.0 volts, an input current of 0.5 milliamps, and an output current of 10 milliamps. What is the power gain? A. 20 B. 40 C. 400 D. 4000

**Last Answer :** Answer: C

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**Description :** The power supplied to a motor is six kilowatts at 120 volts. What is the impedance of the motor? A. 0.05 Ohms B. 0.50 Ohms C. 2.40 Ohms D. 24.00 Ohms

**Last Answer :** Answer: C

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**Description :** 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 ... at 0.8 pf lagging at 220 kV. (A) 5.58MW (B) 80MW (C) 85.58MW (D) 74.42 MW

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**Description :** 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

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**Description :** The per unit impedance of a circuit element is 0.30. If the base kV and base MVA are halved, then the new value of the per unit impedance of the circuit element will be: (A) 0.3 (B) 0.6 (C) 0.003 (D) 0.006

**Last Answer :** 3

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**Description :** What would be the power consumed in the combined parallel section of the circuit shown in the illustration if the source were 30 volts and the resistance for R1 is 10 ohms, R2 is 10 ohms, and R3 is 10 ohms? EL-0032 A. 5 watts B. 10 watts C. 20 watts D. 40 watts

**Last Answer :** Answer: C

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**Description :** What power would be consumed by the series resistor of the circuit shown in the illustration if the source is 30 volts, the resistance of R1 is 10 ohms, R2 is 10 ohms, and R3 is 10 ohms? EL-0032 A. 5 watts B. 10 watts C. 20 watts D. 40 watts

**Last Answer :** Answer: D

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**Description :** What power would be consumed in EACH of the branch resistors of the circuit shown in the illustration if the source is 30 volts, the resistance for R1 is 10 ohms, R2 is 10 ohms and R3 is 10 ohms? EL-0032 A. 5 watts B. 10 watts C. 20 watts D. 40 watts

**Last Answer :** Answer: B

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**Description :** What would be the total power consumed in the circuit shown in the illustration if the source is 30 volts the resistance for R1 is 10 ohms, R2 is 10 ohms, and R3 is 10 ohms? EL-0032 A. 10 watts B. 40 watts C. 45 watts D. 60 watts

**Last Answer :** Answer: D

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**Description :** A transformer steps down 220V to 40 volts. If the secondary turns are 40 then primary turns will be: a. 20 b. 40 c. 120 d. 220

**Last Answer :** d. 220V

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**Description :** In changing from an energy state of -1.51 electron-volts to -3.40 electron-volts, an atom emits a photon whose energy is: w) 1.51 electron-volts x) 1.89 electron-volts y) 3.40 electron-volts z) 4.91 electron-volts

**Last Answer :** ANSWER: X -- 1.89 ELECTRON-VOLTS

761 views

**Description :** A single core cable is designed to work for a single phase system with a peak voltage of 220 kV. The maximum permissible stress in the dielectric is not to exceed 20 kV/mm. For economical size, the overall core diameter of the cable is (A) 28.2 mm (B) 26.4 mm (C) 24.4 mm (D) 22.0 mm

**Last Answer :** A single core cable is designed to work for a single phase system with a peak voltage of 220 kV. The maximum permissible stress in the dielectric is not to exceed 20 kV/mm. For economical size, the overall core diameter of the cable is 22.0 mm

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**Description :** A 3-phase star-connected 75 MVA, 25 kV 3-phase synchronous generator has a synchronous reactance of 1.0 p.u. The per unit value to a 90 MVA base and 30 kV is (A) 2/15 p.u. (B) 5/6 p.u. (C) 1.0 p.u. (D) 1.2 p.u.

**Last Answer :** A 3-phase star-connected 75 MVA, 25 kV 3-phase synchronous generator has a synchronous reactance of 1.0 p.u. The per unit value to a 90 MVA base and 30 kV is 5/6 p.u.

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The corona loss of a 3-phase transmission line is 100 kW at 60 kV/phase and 25 kW at 50 kV/phase....

**Description :** 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

**Last Answer :** 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 40 kV

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**Description :** A 1100 kVA, 11 kV/1.1 kV conventional two-winding transformer is connected as a 12.1 kV/11 kV step-down auto-transformer. The rating of the auto-transformer is (A) 1000 kVA (B) 1100 kVA (C) 11000 kVA (D) 12100 kVA

**Last Answer :** A 1100 kVA, 11 kV/1.1 kV conventional two-winding transformer is connected as a 12.1 kV/11 kV step-down auto-transformer. The rating of the auto-transformer is 12100 kVA

656 views

**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

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**Description :** 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 ... winding protected against earth fault (1) 10.6% (2) 11.6% (3) 10.9% (4) 11.2%

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**Description :** A transformer when supplying a load, maintained at 11 kV across load terminals. When the load was switched off, the terminal voltage becomes 11550 V, what is the voltage regulation at this load? (1) 11.55 % (2) 5.5% (3) 5% (4) 55%

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**Description :** 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

**Last Answer :** 89

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**Description :** An Oil-filled cable has a working stress of ___________ kV/mm. (A) 10 (B) 12 (C) 13 (D) 15

**Last Answer :** Answer : (D) 15

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**Description :** 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

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**Description :** Three single phase transformers are connected in delta-delta to step down a line voltage of 138 kV to 4160 V to supply power to a production plant. The plant draws 21 MW at a lagging power factor of 86 %. Calculate the apparent power ... HV line. (A) 24.4 MVA (B) 48.8 MVA (C) 12.2 MVA (D) 6.1 MVA

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**Description :** 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 ... current. (A) 4.416 ohm (B) 8.8 ohm (C) 2.08 ohm (D) 10.2 ohm

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**Description :** A Phase shift transformer is designed to control 150 MVA on a 230 kV, 3 phase line. The phase angle is variable between zero and 15 deg. Calculate the approximate basic power rating of the transformer. (A) 150 MVA (B) 56 MVA (C) 75 MVA (D) 750 MVA

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**Description :** 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

**Last Answer :** 543A

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**Description :** A 30 MVA, 15 KV, 1500 rpm, 3 phase synchronous generator connected to a power grid has a synchronous reactance of 9 ohm per phase. If the exciting voltage is 12 kV (line to neutral) and the system voltage is 17.3 kV ( ... losses synchronous). (A) 39.952 MW (B) 78.349 MW (C) 16.67 MW (D) 112.89 MW

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**Description :** 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

**Last Answer :** c

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**Description :** A 400/200 volts transformer has pu impedance of 0.05. The HV side voltage required to circulate full load current during short circuit test is

**Last Answer :** A 400/200 volts transformer has pu impedance of 0.05. The HV side voltage required to circulate full load current during short circuit test is 20 V

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**Description :** Express Parcel Post is all about value for money. It costs just INR 25 within the city for 2 kg parcels and INR 40 for towns within 500 km. Above statement is a) True b) False

**Last Answer :** a) True

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**Description :** A lamp of 100W at 200V is supplied current at 100 volts. It will be equivalent to the lamp of: a. 50W b. 40W c. 25W d. 10W

**Last Answer :** A lamp of 100W at 200V is supplied current at 100 volts. It will be equivalent to the lamp of: 25W

233 views

**Description :** A certain transformer has 200 turns in the primary winding, 50 turns in the secondary winding and 120 volts applied to the primary. What is the voltage across the secondary? (A) 30 Volts (B) 480 Volts (C) 120 Volts (D) 60 Volts

**Last Answer :** A certain transformer has 200 turns in the primary winding, 50 turns in the secondary winding and 120 volts applied to the primary. What is the voltage across the secondary? (A) 30 Volts (B) 480 Volts (C) 120 Volts (D) 60 Volts

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**Description :** In a clipper circuit with silicon diode and bias of V volts, the clipping level is (a) 0.7 V (c) V (b) V + 0.7 (d) 2V + 0.7

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