1. Separators are usually placed between opposing plates in leads acid cells to: A. prevent the electrodes from touching B. prevent current flow through the cell C. ensure that the positive and negative electrodes are connected D. help with the polarization effect during discharge 2. Gel-type and paste-type …
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1. A three-phase generating system has an efficiency of around: A. 96% B. 90% C. 66% D. 50% 2. The windings of a three-phase alternator are separated by: A. 90°E B. 120º E C. 180°E D. 360°E 3. Figure shows the stator winding arrangement of …
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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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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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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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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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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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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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1. Look at the following diagram: The above diagram shows the magnetic field produced by a bar magnet. As they expand away from the magnet the magnetic fields: A. become weaker B. gain extra strength C. begin to alternate D. change polarity 2. By convention a …
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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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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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