**Description :** Direct Current (DC) Next Topic : Alternating current (AC)

**Last Answer :** Direct Current (DC) is the unidirectional electric current. Uni meaning is one. And the flow of charge in same direction. We know that conventional current flow from positive terminal of battery to ... The magnitude of DC may constant or vary but direction do not change with respect to time.

**Description :** Alternating current (AC)

**Last Answer :** AC stands for Alternating Current meaning voltage or current that changes polarity or direction respectively over time. An Alternating Current (AC) is an electric current whose magnitude ... energy are known as alternators and are simpler construction than DC electromechanical generators.

**Description :** Does current flow through a capacitor ?

**Last Answer :** Imagine a pipe with a flexible diaphram in the middle separating two haves of the pipe. Now the pipe is filled with air. If you apply a pressure to one end the diaphram will deform ... capacitor, the effects on electrons will be recreated across the boundary. But theres no electrical connection...

**Description :** What kills, current or voltage?

**Last 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

**Description :** A charge of 0.1 C moves past a given point every 0.01 s. How much is the current?

**Last Answer :** The current is 10.0A. 1ampere = 1 Coulomb per 1 second. 0.1Coulombs ÷ 0.01seconds = 10.0amperes.

**Description :** Describe the difference between direct and alternating current.

**Last Answer :** Direct current is the flow of electricity or charge in one direction.. Alternative current is the flow of charge that doesn't flow in one direction.

**Description :** Explain why potential difference is necessary to produce current in a circuit.

**Description :** Capacitive current

**Last Answer :** Capacitive current formula

**Description :** How to find total impedance Z, current I and Impedance angle ?

**Last Answer :** How to find total impedance Z, current I and Impedance angle ?

**Description :** Why inductor current lags inductor voltage ?

**Last Answer :** Inductor is a wire wounding structure having a core material it induces emf which is opposite to the voltage supply and proportional to rate of change of current so current lags the voltage in inductor

**Description :** Explain lagging quantity and leading quantity, explain this concept with voltage and current waveform

**Last 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.

**Description :** List out any four effects of electric current used in measuring instruments & write name of meter working on it.

**Last Answer :** Effects of Electric Current used in measuring instruments: 1. Magnetic Effect: PMMC and Moving Iron type Ammeters, voltmeter and Dynamometer type wattmeters etc. 2. Electromagnetic induction ... . Electrostatic effect: Voltmeters. 5. Hall Effect: Flux meter, Poynting vector wattmeter.

**Description :** State various effects of electric current and explain any one.

**Last Answer :** Effects of Electric Current: 1. Magnetic Effect: When a current is passed through a conductor, magnetic field is produced round the conductor. Due to this field when current carrying ... The rise in temperature is converted into elongation of hot wire element causes displacement of pointer.

**Description :** In a series R-C circuit, with the increase in frequency, current (A) Reduces (B) Increases (C) Does not change (D) Becomes zero

**Last Answer :** In a series R-C circuit, with the increase in frequency, current Increases

**Description :** A 1000Ohm, 1 Watt resistor can safely pass a current of

**Last Answer :** A 1000 Ohm, 1 Watt resistor can safely pass a current of 30 mA

**Description :** Step-down transformer converts high voltage and low current into: (A) How voltage and high current (B) High voltage and low current (C) Low voltage and high current (D) None of the above

**Last Answer :** Step-down transformer converts high voltage and low current into: Low voltage and high current

**Description :** Which of the following is the least expensive protection for over current in low voltage system? (A) Rewireable fuse (B) Isolator (C) Oil Circuit breaker (D) Air break circuit breaker

**Last Answer :** Which of the following is the least expensive protection for over current in low voltage system? (A) Rewireable fuse (B) Isolator (C) Oil Circuit breaker (D) Air break circuit breaker

**Description :** For a round wire, the approximate value of fusing current is given by

**Last Answer :** For a round wire, the approximate value of fusing current is given by K√d3

**Description :** A current controlled voltage source is equivalent to : (A) series voltage feed -back amplifier (B) shunt current feed -back amplifier (C) shunt voltage feed -back amplifier (D) series current feed -back amplifier

**Last Answer :** A current controlled voltage source is equivalent to : shunt voltage feed -back amplifier

**Description :** Which of the following can reduce the Eddy current losses? A) By making the core of a stack of plates electrically insulated from each other B) By making the core of solid block C) By increasing the applied voltage D) None of these

**Last Answer :** Which of the following can reduce the Eddy current losses? A) By making the core of a stack of plates electrically insulated from each other B) By making the core of solid block C) By increasing the applied voltage D) None of these

**Description :** A network that consists of at least a voltage source or current source is called A) Active network B) Ideal network C) Sourced network D) Outsourced network

**Last Answer :** A network that consists of at least a voltage source or current source is called Active network

**Description :** The current flow in a battery is due to ______ A) movement of ions B) movement of protons C) movement of holes D) movement of neutrons

**Last Answer :** The current flow in a battery is due to movement of ions

**Description :** A ferrite core has less eddy current loss than an iron core because?

**Last Answer :** A ferrite core has less eddy current loss than an iron core because ferrites have high hysteresis.

**Description :** 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.

**Last Answer :** 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 20 Vs

**Description :** When an alternating current passes through an ohmic resistance the electrical power converted into heat is?

**Last Answer :** When an alternating current passes through an ohmic resistance the electrical power converted into heat is true power.

**Description :** The equation of 50 Hz current sine wave having r.m.s. value of 60 A is?

**Last Answer :** (60*√2)Sin(2π*50*t)

**Description :** The frequency of an alternating current is?

**Last Answer :** The frequency of an alternating current is the number of waves passing through a point in one second.

**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 :** In the case of an unsymmetrical alternating current the average value must always be taken over?

**Last Answer :** In the case of an unsymmetrical alternating current the average value must always be taken over the whole cycle.

**Description :** In a loss-free R-L-C circuit the transient current is?

**Last Answer :** In a loss-free R-L-C circuit the transient current is sinusoidal.

**Description :** Inductance affects the direct current flow?

**Last Answer :** Inductance affects the direct current flow at the time of turning on and off.

**Description :** The r.m.s. value of a sinusoidal A.C. current is equal to its value at an angle of______degrees.

**Last Answer :** 45

**Description :** Why does induction motor have high starting current?

**Last Answer :** In induction motor , the flux produce is quadrature to the applied voltage. Since when we are going to start motor , there is no flux present inside . So in order to lets say compensate it ... times of current to further increase flux. So that is reason for high starting current in induction motor

**Description :** What is the relationship between power and current?

**Last Answer :** P = I2R Where P = power I = Current R = Resistance This the relationship between current and power.

**Description :** What happens to the resistance when the current increases?

**Last Answer :** Resistance reduces when current increases.

**Description :** How eddy current can be minimized?