Can you help by answering this question?

Pilot relaying schemes are used for the protection of

22 views
in Electrical Engineering by
The voltage across a coil, when di/dt = 20 mA/s and L = 8 H, is: A. 16 mV B. 160 mV C. 1.6 mV D. 2.5 mV

1 Answer

0 votes
by

The voltage across a coil, when di/dt = 20 mA/s and L = 8 H, is: 160 mV

Related questions

0 answers 23 views

A diode D, resistor R and inductor L and a switch S are connected in series.When a voltage V is applied across the circuit and switch is put on, the voltage across L changes as  A) V(1-exp(-t R/L)) B) Vexp(-t R/L) C) Ldi/dt +Ri D) V(1-t R/L)

asked Apr 9, 2018 in Electronics Engineering by Shimroz123
1 answer 13 views

In an AC circuit, the voltage across R, L and C are 30 V, 60 V and 20 V respectively. The applied voltage is (A) 70 V (B) 50 V (C) 60 V (D) 100 V

asked May 12, 2018 in Electrical Engineering by Shimroz123
1 answer 61 views

In an ac series RLC circuit, the voltage across R and L is 20 V; voltage across L and C is 9 V and voltage across RLC is 15 V. What is the voltage across C?

asked May 1, 2018 in Network Analysis by Shimroz123
1 answer 50 views

When there is 12 mA of current through a 1.2 k ohms resistor, the voltage across the resistor is? A.14.4 V B.1.4 V C.100 V D.10 V

asked May 15, 2018 in Basic concepts by Shimroz123
1 answer 22 views

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 in Electrical Engineering by Shimroz123
1 answer 22 views

The induced voltage across a coil with 250 turns that is located in a magnetic field and is changing at a rate of 8 Wb/s is A. 1,000 V B. 2,000 V C.31.25 V D. 3,125 V

asked Apr 12, 2018 in Electrical Engineering by Shimroz123
1 answer 4 views

What is the value of Inductance of a coil that induces 20 V when the current through the coil changes from 12 to 20 A in 2 seconds? A. 2 H B. 3 H C. 4 H D. 5 H 

asked Apr 12, 2018 in Electrical Engineering by Shimroz123
1 answer 39 views

The initial rate of rise of current through a coil of inductance 10 H when suddenly connected to a D.C. supply of 200 V is_______Vs.

asked Mar 25, 2018 in Electrical Engineering by Shimroz123
0 answers 21 views

The emf induced in a coil is 1 volt when current in it changes from 0 to 100 mA in time 10mS. Its inductance (in mH) value is  A) 10 B) 50 C) 100 D) 1000

asked Apr 9, 2018 in Electronics Engineering by Shimroz123
1 answer 18 views

A moving coil meter has a resistance of 3 Ω and gives full scale deflection with 30 mA. To measure voltage up to 300 V, the external resistance to be connected in series with the instrument is (A) 9997 Ω (B) 10000 Ω (C) 997 Ω (D) 10003 Ω

asked Apr 28, 2018 in Power Electronic Controlled Drives by Shimroz123
1 answer 18 views

The voltage induced across a certain coil is 200 mV. A 1200 resistor is connected to the coil terminals. The induced current will be: A. 1.7 mA B. 16 mA C. 12 mA D. 120 mA

asked Apr 12, 2018 in Electrical Engineering by Shimroz123
0 answers 39 views

The voltage applied to the H.V. side of a transformer during S.C. test is 2% of the rated voltage. The core loss as the fraction of its rated core loss is (a) 4% (b) 0.4% (c) 0.25% (d) 0.04%

asked May 25, 2018 in Transformer by Shimroz123
1 answer 11 views

When the turns ratio of a transformer is 20 and the primary ac voltage is 12 V, the secondary voltage is? A.12 V B.120 V C.240 V D.2,400 V

asked May 15, 2018 in Basic concepts by Shimroz123
1 answer 25 views

If resistance is 20 Q. and inductance is 27 in a R-L series circuit, then time constant of this circuit will be?

asked Mar 25, 2018 in Electrical Engineering by Shimroz123
0 answers 12 views

What is the pitch factor of a 4 pole alternator having 36 slots and a coil span of 1 to 8?  (A) 140° (B) 80° (C) 20° (D) 40°

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
1 answer 40 views

When 7/0.029 V.I.R cable is carrying 20 A, a drop of 1 V occurs every 12 m. The voltage drop in a 100 m run of this cable when it is carrying 10 A is nearly  (a) 4.2 V (b) 3.2 V (c) 1.2 V (d) 0.42 V

asked Apr 25, 2018 in Electrical Engineering by Shimroz123
0 answers 16 views

A dynamometer type wattmeter with its voltage coil connected across the load side of instrument reads 250 W. If the load voltage be 200 V, what power is being taken by load? The voltage coil has resistance of 2000 Ω. (1) 200 W (2) 215W (3) 230 W /(4) 245 W

asked Apr 11, 2018 in Electrical Engineering by Shimroz123
1 answer 17 views

In a series resonant circuit, maximum voltage across L occurs at  (a) Resonant frequency (b) Slightly below resonant frequency (c) Slightly above resonant frequency (d) At a frequency where I is maximum

asked Apr 23, 2018 in Electrical Engineering by Zeeshan
0 answers 28 views

A choke coil having resistance RΩ and of inductance L Henry is shunted by a capacitor of C farads. The dynamic impedance of the resonant circuit would be:  (A) R/LC (B) C/RL (C) L/RC (D) 1/RLC 

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
1 answer 47 views

The potential coil of a single phase dynamometer wattmeter has 4840 Ohm resistance. Voltage across the load is 220 V. With the potential coil connected on the load side, the meter indicates 100 W. Approximate percentage error due to wattmeter connection is (A) 11% (B) 9% (C) 1.1% (D) 3%

asked Apr 25, 2018 in Instrumentation and control by Shimroz123
1 answer 20 views

A coil of inductance 240 mH and resistance 75 Ohm is connected in parallel with a capacitor across a 30 V, variable frequency supply. The current drawn by the circuit is found to be minimum when the supply frequency is 1 kHz. The approximate values of Q-factor and bandwidth are, respectively (A) 40, 400 Hz (B) 10, 100 Hz (C) 20, 50 Hz (D) 50, 20 Hz

asked Apr 25, 2018 in Electrical Engineering by Shimroz123
0 answers 21 views

A dc shunt generator has a speed of 800 rpm when delivering 20 A to the load at the terminal voltage of 220V. If the same machine is run as a motor it takes a line current of 20A from 220V supply. The speed of the machine (in rpm) will be:  (A) 800 (B) more than 800 (C) less than 800 (D) none of the above

asked Apr 9, 2018 in Electrical Engineering by Shimroz123
1 answer 22 views

What is the charge on each capacitor when a 150 V is applied across two capacitors with values 5 μF and 10 μF, connected in series? A) 500 μC B) 0.5 μC C) 0.5 C D) None of these

asked Apr 29, 2018 in Electrical Engineering by Shimroz123
1 answer 11 views

The power consumed by a coil is 300 W when connected to a 30 V dc source and 108 W when connected to a 30 V ac source. The reactance of the coil is

asked Apr 23, 2018 in Electrical Engineering by Zeeshan
1 answer 36 views

5xl016 electrons pass across the section of a conductor in 1 minute 20 sec. The current flowing is 

asked Mar 31, 2018 in Electrical Engineering by Shimroz123
0 answers 22 views

In a series RLC circuit, the rms value of voltage across the resistor is 30 V, across the inductor is 60 V and across the capacitor is 20 V. The rms supply voltage would be (A) 110 V (B) 10 V (C) 220 V (D) 50 V

asked Apr 14, 2018 in Electrical Engineering by Shimroz123
0 answers 13 views

If the load current and flux of a DC motor are held constant, and voltage applied across its armature is increased by 10%, its speed will:  (A) Decrease by 10%. (B) Remain unchanged. (C) Increase by 10%. (D) Increase by 20%. 

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

The 8O85 assembly language instruction that stores the contents of H and L registers into the memory locations 2050H and 2051H, respectively, is: A) SPHL 2050H B) SPHL 2051H C) SHLD 2050H D) STAX 2050H

asked Jun 17, 2018 in Microprocessors and Microcontrollers by Shimroz123
1 answer 10 views

The current through a flashlight bulb is 40 mA and the total battery voltage is 4.5 V. The resistance of the bulb is approximately? A.112 ohms B.11.2 ohms C.1.2 ohms D.18 ohms

asked May 15, 2018 in Basic concepts by Shimroz123
2 answers 196 views

What happens to current flow in a capacitive circuit when the DC voltage across the capacitor is approximately equal to the source voltage?

asked May 29, 2018 in Capacitance by Shimroz123
1 answer 27 views

When the voltage across a battery is measured using a D.C potentiometer, the reading shows 1.08 V. But when the same voltage is measured using a Permanent Magnet Moving Coil (PMMC) voltmeter, the voltmeter reading shows 0.99 V. If the resistance of the voltmeter is 1100 Ohm , the internal resistance of the battery, in Ohm , is (A) 150 (B) 100 (C) 50 (D) 200

asked Apr 26, 2018 in Electrical Measurements and Instrumentation by Shimroz123
1 answer 15 views

What is the capacitance when a capacitor passes a current of 31.43 mA when supplied with 40 V AC with a frequency of 1000 Hz? A) 0.125 F B) 0.125 μF C) 1257.2 μF D) None of these

asked Apr 29, 2018 in Electrical Engineering by Shimroz123
0 answers 9 views

If a current of 500 mA charges a dielectric for 2 s, how much charge is stored in the dielectric?

asked Jul 1 by Shimroz123
1 answer 24 views

A transformer at 25 Hz develops 20 W hysteresis loss and 50 W eddy current loss. If the applied voltage and frequency are doubled, the new core losses are (A) 140 W (B) 180 W (C) 240 W (D) 480 W

asked Apr 28, 2018 in Electrical Engineering by Shimroz123
1 answer 24 views

When both the inductance and resistance of a coil are doubled the value of?

asked Mar 25, 2018 in Electrical Engineering by Shimroz123
1 answer 11 views

Twelve volts are applied across a resistor. A current of 3 mA is measured. What is the value of the resistor? A.4 ohms B.400 ohms C.4 kohms D.4.4 ohms

asked May 15, 2018 in Basic concepts by Shimroz123
1 answer 101 views

The loop transfer of a system is G(s) H(s) = 5/(s+1) (2s+1)(3s+1) which has the phase crossover frequency fc = 0.16 Hz. The gain margin (dB) of the system is  (a) 6 (b) 4 (c) 2 (d) 0

asked May 15, 2018 in Control System by Shimroz123
0 answers 61 views

An energy meter has a constant of 600 rev/kWh. If the meter makes 10 revolutions in 20 s, what is the load in kW?  (A) 0.75 kW (B) 1.5 kW (C) 3 kW (D) 6 kW 

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
0 answers 15 views

If a forward voltage (less than forward breakover voltage) is suddenly applied across anode and cathode of a thyristor, it may result into   (a) Damage to the thyristor (b) Premature triggering of the thyristor because of high dV/dt (c) Reduced holding current of the thyristor (d) All of the above  

asked Apr 10, 2018 in Electrical Engineering by Shimroz123
2 answers 52 views

If resistance is 8 Ohm and current is 16 ampere then what will be the voltage and power?

asked Oct 21, 2017 in Electrical Engineering by Quiz
0 answers 65 views

What happens to the angle between current and voltage, when a small capacitance is added in series with a highly inductive circuit?  (A) Increases (B) Remains same as earlier angle (C) Decreases (D) Becomes indeterminant

asked Apr 5, 2018 in Electrical Engineering by Shimroz123
1 answer 75 views

The power consumed in a circuit element will be least when the phase difference between the current and voltage is?

asked Mar 24, 2018 in Electrical Engineering by Shimroz123
0 answers 27 views

A series R-L circuit is suddenly connected to d.c. voltage source of V volts. The current in this series circuit, just after the switch is closed, is equal to (1) Zero (2) V/L (3) V/C (4) V.L/C 

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

A Hurwitz polynomial D(s) must satisfy two conditions. One is the polynomial is real when s is real. What is the other condition ?

asked Apr 23, 2018 in Electrical Engineering by Shimroz123
0 answers 62 views

The ammeter reading connected across a CT secondary is 3 A and the voltage reading connected across a PT is 90 V. If the specification of the CT and PT are respectively 1000 A/5 A and 6.6 kV/110 V, What is the actual current and voltage of the line? 

asked Apr 3, 2018 in Lesson 2 Generation, Transmission and Distribution of Electric Power an Overview by Shimroz123
0 answers 12 views

 For identical total transmitted power, the ratio of S/N for wide band FM to S/N of DSB-AM (with ma=1) is : ( Given fm = 15 KHz & frequency. deviation =+/- 75 KHz) a. 112.5 b. 300 c. 75 d. 450

asked Apr 12, 2018 in Electronics Engineering by Shimroz123
1 answer 40 views

What is the stored energy when 200 V is applied across a 7 μF capacitor? A) 1400 Joules B) 0.7 Joules C) 0.14 Joules D) None of these

asked Apr 29, 2018 in Electrical Engineering by Shimroz123
1 answer 16 views

An alternator is delivering rated current at rated voltage and 0.8 power-factor lagging. For delivering rated current at rated voltage and 0.8 poWer—factor leading, the required excitation will be:  (A) less  (B) more (C) more or less (D) the same

asked Apr 9, 2018 in Electrical Engineering by Shimroz123
0 answers 16 views

The current coil of a wattmeter is connected to the C.T. of R phase. Its potential coil is connected across Y & B phases. The wattmeter measures (a) active power in R phase (b) active power of Y-phase (c) reactive power in R-phase (d) power proportional to 3-phase power if the load is balanced 

asked May 25, 2018 in Electrical Measurements and Instrumentation 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

8,450 questions

7,047 answers

132 comments

3,084 users

...