Description : if voltage is 230 Volts , frequency is 50 Hz and current is 1 ampere then what will be the resistance?
Answer :
As V = 230v and I = 1A Therfore by ohm's law V =IR R = V/I =230/1 =230 ohm
asked
Dec 4, 2017
by
anonymous
Description : For a balanced three phase star connected load for which line voltage is 230V and per phase resistance and reactance is 6 Ohm and 8 Ohm respectively. Calculate: 1) phase voltage 2) line current 3) power factor 4) total power absorbed
asked
Aug 12, 2018
by
anonymous
Answer :
The mechanical power developed by a shunt motor will be maximum when the ratio of back e.m.f. to applied voltage is 0.5.
asked
Mar 20, 2018
by
anonymous
Description : Is the power line voltage available in our homes a dc or an ac voltage?
Answer :
The power line voltage available in our homes is AC. Mobile dwellings are the most commonly DC-supplied homes and even then they tend to include AC supply for heavier loads.
asked
Jun 29, 2019
by
anonymous
Description : An independent voltage source in series with an impedance ZS=R+jXS delivers a maximum average power to a load impedance ZL when A) ZL = R B) ZL = jXS C) ZL = R-jXS D) ZL = R+jXS
Answer :
An independent voltage source in series with an impedance ZS=R+jXS delivers a maximum average power to a load impedance ZL when ZL = R-jXS
asked
Jun 18, 2018
by
anonymous
Description : Sinusoids find amplitude, period, frequency, voltage (Problem 1)
Answer :
Sinusoids find amplitude, period, frequency, voltage (Problem 1)
asked
Mar 29, 2020
by
anonymous
Description : Problem on electrical power and energy 2
Answer :
Problem on electrical power and energy 2
asked
May 16, 2019
by
anonymous
Description : Problem on electrical power and energy 1
Answer :
Problem on electrical power and energy 1
asked
May 16, 2019
by
anonymous
Description : Problem on electrical power and energy 7
Answer :
Problem on electrical power and energy 7
asked
May 16, 2019
by
anonymous
Description : Problem on electrical power and energy 6
Answer :
Problem on electrical power and energy 6
asked
May 16, 2019
by
anonymous
Description : Problem on electrical power and energy 5
Answer :
Problem on electrical power and energy 5
asked
May 16, 2019
by
anonymous
Description : A d.c. source has an open circuit voltage of 30 V and an internal resistance of 1.5 Ohm. A resistive load is connected to the source. Maximum power dissipated in the load is (A) 300 W (B) 150 W (C) 45 W (D) 20 W
Answer :
A d.c. source has an open circuit voltage of 30 V and an internal resistance of 1.5 Ohm. A resistive load is connected to the source. Maximum power dissipated in the load is 150 W
asked
Apr 25, 2018
by
anonymous
Description : The power consumed in a circuit element will be least when the phase difference between the current and voltage is?
Answer :
The power consumed in a circuit element will be least when the phase difference between the current and voltage is 90°.
asked
Mar 24, 2018
by
anonymous
Description : About trnsformer
Answer :
Acc to Ohms law V=IR but it is only applicable when our resistance R is constant, as in case of transformer we take impedence which is equivalent to resistance is not constant it varies with system parameters that why Ohms law not applicable in case of transformer
Answer :
Find power delivered by voltage source
asked
Mar 21, 2020
by
anonymous
Description : A transformer has negative voltage regulation when its load power factor is (1) Zero (2) Unity (3) Leading (4) Lagging
Answer :
Leading
asked
Apr 30, 2018
by
anonymous
Description : In voltage source converter based HVDC transmission system the active power is controlled by changing (A) phase angle of the converter ac input voltage (B) supply frequency of the converter ac input voltage (C) magnitude of the converter ac input voltage (D) DC voltage at the inverter terminals
Answer :
In voltage source converter based HVDC transmission system the active power is controlled by changing phase angle of the converter ac input voltage
asked
Apr 28, 2018
by
anonymous
Description : For a 15-bus power system with 3 voltage controlled buses, the size of Jacobian matrix is
Answer :
For a 15-bus power system with 3 voltage controlled buses, the size of Jacobian matrix is 25 x 25
asked
Apr 27, 2018
by
anonymous
Answer :
The contacts of high voltage switches used in power system are submerged in oil. The main purpose of the oil is to extinguish the arc.
asked
Mar 20, 2018
by
anonymous
Description : Minimum voltage regulation occurs when the power factor of the load is?
Answer :
Minimum voltage regulation occurs when the power factor of the load is leading.
asked
Mar 19, 2018
by
anonymous
Description : In an alternator at lagging power factor the generated voltage per phase as compared to that at unity power factor?
Answer :
In an alternator, at lagging power factor the generated voltage per phase as compared to that at unity power factor must be more than terminal voltage.
asked
Mar 18, 2018
by
anonymous
Description : Why high voltage can reduce power loss?
Answer :
when voltage has increased due to reduced current flow, thus power loss given by ( I^2R) will be low due to reduced current(I^2) provided that resistance (R) is constant.
asked
Mar 10, 2018
by
anonymous
Description : Why high voltage is used in power transmission?
Answer :
The primary reason that power is transmitted at high voltages is to increase efficiency. ... The lower current that accompanies high voltage transmissionreduces resistance in the conductors aselectricity flows ... This means that thin, light-weight wires can beused in long-distance transmission.
asked
Mar 10, 2018
by
anonymous
Description : Justify. Power MOSFET is operated at high enough gate source voltage to minimize the conduction losses.
Answer :
MOSFET is metal oxide field effect transistor. MOSFET is a voltage controlled device. MOSFET is majority carrier device. MOSFET are of two one is n-channel MOSFET and p-channel MOSFET. Gate, ... . Hence, power MOSFET is operated at high enough gate-source voltage to minimize the conduction losses.
asked
Dec 7, 2017
by
anonymous
Description : If 3000 kW power is to be transmitted over a distance of 30 km, the desirable transmission voltage will be. (A) 11 kV (B) 33 kV (C) 66 kV (D) 132 kV
Answer :
By
asked
May 8, 2018
by
anonymous
Description : The kVA rating of Three-phase transformer with Voltage = 200V and Current = 100A will be : (A) 34.64 kVA (B) 75 kVA (C) 20 kVA (D) None of the above
Answer :
The kVA rating of Three-phase transformer with Voltage = 200V and Current = 100A will be : 34.64 kVA
asked
May 8, 2018
by
anonymous
Description : The power flow problem mathematical model for a linear transmission network (A) is non-linear (B) is linear (C) considers time variation of generation (D) does not consider tap-changing transformers
Answer :
The power flow problem mathematical model for a linear transmission network is non-linear
asked
Apr 28, 2018
by
anonymous
Description : what will be the capacitance if three capacitors connected in parallel each having value of 0.5 micro Farad ?
Answer :
the total capacitace when connected in parallel Tc=total capacitor c1=c2=c3=0.5uf Tc=c1+c2+c3 Tc=1.5uf
asked
Dec 11, 2017
by
anonymous
Description : An SSB transmitter produces a peak-to-peak voltage of 200 V across a 100 Ω antenna load. What is the Peak Envelope Power? A) 49.98 W B) 79.98 W C) 99.96 W D) 199.93 W
Answer :
An SSB transmitter produces a peak-to-peak voltage of 200 V across a 100 Ω antenna load. What is the Peak Envelope Power? A) 49.98 W B) 79.98 W C) 99.96 W D) 199.93 W
asked
Jun 18, 2018
by
anonymous
Description : Problem on resistance and resistivity 8
Answer :
Problem on resistance and resistivity 8
asked
May 18, 2019
by
anonymous
Description : If an incandescent lamp of 80 ohms resistance takes a current of 0.75 ampere, what voltage is required to light it? A.45 volts B.60 volts c.23 volts D.None of these
Answer :
V=IR = 80*0.75 = 60 volts
Description : A single-phase voltage source square -wave inverter feeds pure inductive load. The waveform of the load current will be
Answer :
A single-phase voltage source square -wave inverter feeds pure inductive load. The waveform of the load current will be triangular
asked
Apr 29, 2018
by
anonymous
Answer :
Due to no potential difference between the ends of the circiut there is no existance of current
Description : A network contains linear resistors and ideal voltage sources. If values of all the resistors are doubled then the voltage across each resistor will
Answer :
A network contains linear resistors and ideal voltage sources. If values of all the resistors are doubled then the voltage across each resistor will not change
asked
Apr 29, 2018
by
anonymous
Description : The product of apparent power and cosine of the phase angle between circuit voltage and current is?
Answer :
In parllpar reasonans RLC circuit the current is
asked
Mar 25, 2018
by
anonymous
Description : If a boy rows 8 km downstream in 6 hours and 4 km upstream in 4 hours then how long will he take to cover 16 km in stationary (still) water? A) 8 B) 14 C) 22 D) 16
Answer :
Answer: B Explanation: Distance covered in downstream = 8 km Time taken in downstream = 6 hours. Rate of downstream = 8/6=4/3 km/hr Distance covered in upstream = 4 km Time taken in upstream = 4hours. ... 3+1) = 7/6km/hr Time Taken to cover 16 km in still water = 16*6/7=14hrs (approximately)
Answer :
In a D.C. shunt motor, under the conditions of maximum power, the current in the armature will be more than full-load current.
asked
Mar 20, 2018
by
anonymous
Description : When an alternating current passes through an ohmic resistance the electrical power converted into heat is?
Answer :
When an alternating current passes through an ohmic resistance the electrical power converted into heat is true power.
asked
Mar 25, 2018
by
anonymous
Description : A network is said to be under resonance when the voltage and the current at the network input terminals are (A) in phase (B) out of phase (C) in phase quadrature (D) in phase, and have equal magnitudes
Answer :
A network is said to be under resonance when the voltage and the current at the network input terminals are in phase
asked
Apr 28, 2018
by
anonymous
Description : What is the RMS voltage in a series RL circuit, if the voltage across R and L is 256 V and 192 V respectively? A) 320 V B) 448 V C) 64 V D) None of these
Answer :
What is the RMS voltage in a series RL circuit, if the voltage across R and L is 256 V and 192 V respectively? A) 320 V B) 448 V C) 64 V D) None of these
asked
Apr 29, 2018
by
anonymous
Description : What kills, current or voltage?
Answer :
Current would kill. You can actually have thousands of bolts going through you and not even know it. Yes you probably know already voltage is current times resistance. Since your body is a resistor it would take just a small amount of current to create a very high voltage
asked
Aug 25, 2019
by
anonymous
Description : Define pinch off voltage and drain resistance of FET.
Answer :
1 . Pinch-off Voltage: It is the value of the drain to source voltage VDS at which the drain current ID reaches its constant saturation value. Any further increase in VDS does not have any ... drain to source voltage to the change in drain current. It is also called AC/dynamic drain resistance.
asked
Sep 5, 2018
by
anonymous
Answer :
If the current in a capacitor leads the voltage by 80°, the loss angle of the capacitor is 10°.
asked
Mar 21, 2018
by
anonymous
Description : If the field of synchronous motor is under excited, power factor will be?
Answer :
If the field of synchronous motor is under excited, power factor will be lagging.
asked
Mar 18, 2018
by
anonymous
Description : A voltage source inverter will have better performance if its (1) load inductance is small and source inductance is large. (2) both load and source inductance are small. (3) both load and source inductances are large. (4) load inductance is large and source inductance is small.
Answer :
A voltage source inverter will have better performance if its load inductance is large and source inductance is small.
asked
Apr 30, 2018
by
anonymous
Description : Which of the following theorems enables a number of voltage (or current) source to be combined directly into a single voltage (or current) source. (1) compensation theorem (2) reciprocity theorem (3) superposition theorem (4) Millman's theorem
Answer :
Which of the following theorems enables a number of voltage (or current) source to be combined directly into a single voltage (or current) source. (1) compensation theorem (2) reciprocity theorem (3) superposition theorem (4) Millman's theorem
asked
Apr 29, 2018
by
anonymous
Description : What is the relationship between power and resistance?
Answer :
P = I2R Where P = power I = Current R = Resistance
asked
Mar 15, 2018
by
anonymous
Description : Draw the Delta connected three phase system showing all the voltages and currents. Write the power equation.
asked
Aug 11, 2018
by
anonymous
Description : Explain lagging quantity and leading quantity, explain this concept with voltage and current waveform
Answer :
When two alternating quantities attain their respective zero or peak values simultaneously, the quantities are said to be in-phase quantities. When the quantities do not attain their respective zero or ... current is leading the voltage or the voltage is said to be lagging behind the current.
asked
Sep 7, 2018
by
anonymous