AC Circuits MCQs with Answers

AC Circuits MCQs with Answers

1. With regards to measuring current and voltage in an AC circuit, modern AC instruments are calibrated to read:    A.  RMS values B.  peak values C.  average values D.  form factor values   2. The current waveform for a purely resistive circuit:    A.  leads the voltage by 90 …

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Alternating Current (AC) MCQs with Answers

Alternating Current (AC) MCQs with Answers

1. The only AC waveform that produces a current flow with the same waveform as the voltage is the:    A.  sine wave B.  symmetrical square wave C.  sawtooth D.  asymmetrical square wave   2. Look at the following diagram:     The waveshape shown in the diagram is:    …

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Capacitors MCQs with Answers

Capacitors MCQs with Answers

1. A capacitor consists of two conducting surfaces called plates, separated by an insulating material called the:    A.  dielectric B.  conductor C.  electrode D.  trielectric   2. Capacitance is the measure of the ability of a capacitor to:    A.  conduct a direct current B.  hold an electric charge …

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Inductors MCQs with Answers

Inductors MCQs with Answers

1. In electric circuits, ‘inductance’ is the property of a circuit which:    A.  produces a voltage in a conductor B.  causes the circuit current to increase C.  remains at a constant value at switch on and switch off D.  prevents any opposition to voltage flow   2. Inductors have …

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Resistors and Resistance MCQs with Answers

Resistors and Resistance MCQs with Answers

1. Resistance can be described as the:    A.  opposition to current flow B.  resist rate of the voltage C.  current acceptability of a voltage D.  opposition to voltage flow   2. The resistance of a material is most commonly determined by four factors-length, cross-sectional area, type of material and:  …

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DC Circuits MCQs with Answers

DC Circuits MCQs with Answers

1. The minimal electrical circuit must contain three parts-a source, a path and a:    A.  load B.  battery C.  circuit D.  supply   2. The source of supply of an electrical circuit is:    A.  always an AC network B.  where the energy comes from C.  the part of …

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Electrochemistry MCQs with Answers

Electrochemistry MCQs with Answers

1. In the electroplating process an external voltage is applied across a pair of electrodes, causing:    A.  a current to flow through an electrolyte B.  an electroplate to form on an electrolyte C.  an alternating voltage in a magnetic chemical D.  a chemical to produce a negative voltage on …

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Basic Electrical Engineering MCQs with Answers 1

1. Matter can exist in any one of four states—solid, liquid, gas and:  A.  plasma B.  molecules C.  air D.  conductance   2. The smallest particle into which any one chemical can be divided without changing the characteristics of that chemical is called:  A.  an atom B.  a molecule C.  …

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Efficiency of DC Motor and DC Generator

dc motor and dc generator efficiency

This guide covers efficiency and losses of DC Machines (Motor and Generator) which include Copper, Core, Brush, Mechanical (Friction and Windage), and Stray losses. Losses in DC machines (motor and generator) include friction, windage and electrical losses. Friction is present in all rotating machinery. Windage is present because of air …

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Commutation in DC Generator

Commutation in DC Generator

The voltage induced in a single coil of a DC generator is alternating. A commutator is therefore necessary to ensure that the current in the external circuit always flows in the one direction. During the brief interval when a coil is short-circuited by a brush, the current in the coil …

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Electric Motor Drives Questions and Answers

Electric Motor Drives Questions and Answers

Motor Drives Define and describe motor drives. A motor drive is an electronic unit designed to control the speed of a motor using solid- state components. Motor drives may be AC or DC drives. In addition to turning motors on and off and providing overload protection, motor drives also provide …

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DC Motor Questions and Answers

DC Motor Questions and Answers

DC Motor Operation Define motor and explain the electron flow motor rule. A motor is a machine that converts electrical energy into mechanical energy by means of electromagnetic induction. The electron flow motor rule is used to determine the direction of motion of a current carrying conductor in a magnetic …

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Electromechanical Relay Questions Answers

Electromechanical Relay Questions Answers

Define relays and explain how they function. A relay is a device that controls one electrical circuit by opening and closing contacts in another circuit. Relays have traditionally been used in machine tool control, industrial assembly lines, and commercial equipment. Relays are used to switch starting coils in contactors and …

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Electrical Safety Questions Answers

Electrical Safety Questions Answers

Electrical Safety State four factors that determine the severity of an electrical shock. The severity of an electrical shock depends on the amount of electric current in milliamps (mA) that flows through the body, the length of time the body is exposed to the current flow, the path the current …

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