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ELECTRICAL CRAFT HELPER TEST|105 QUESTIONS AND ANSWERS|LATEST 2025-2026|A+ GRADED
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a molecule of matter can be divided chemically into smaller particles called? atoms matter consisting of all the same kind of atoms is called an? element matter consisting of two or more different kinds of atoms is called a? compound the negative charge of a single electron is called a? unit electrical charge most of the mass of an atom is in the? nucleus
when an atom gains an electron, it is called? negative ion copper is a good conductor, because the copper atom loosely holds it's? valence gold and silver are good conductor of electricity, because the outer orbits have? one electron when teo negatively charged rods are brought together, they? repel each other one ampere is equal to? 1 coulomb flowing per second
moving and contact other materials the charges on the surface of a liquid in a container can be made harmless if the container is? purged greater static charges are developed on smooth surfaced materials than on rough surfaced materials because of the? larger surface contact what is applied to rubber or that leather belts to prevent the generation of static charges? a conductive dressing the vest way to remove static electricity from machines is to? ground the framework
dust can be removed from the and in a plant by the use of a? electrostatic precipitation the six primary methods of producing a voltage are chemical action , magnetism, friction, heat, light, and pressure electricity is produced by chemical action in a?p storage battery cell through which of the following do electrons move in storage battery cell? electrolyte in which type of cell does the chemical action dissolve the negative plate, which cannot be recharged? hot cell
what is the purpose of a microphone convert sound waves into electrical signals the two points of maximum attraction on a magnet are called? magnetic materials how do magnetic lines of force always arrange themselves? form closed loops when a permanent magnet is broken into pieces, what happens to each piece? becomes a separate magnet what is a coil of wire with an iron core called electromagnet
how many ampere-turn does a coil with 200 turns of wire and 2 amperes of current have? 400 the resistance to magnetic flux is called reluctance what will serve as an effective magnetic shield against magnetic influence an iron or steel casing what is the MKS unit for magnetic flux weber the process by which metals are demagnetized is called degaussing
without a given potential, how do free elections in a conductor constantly move? in a random manner the instrument that measures electrical current is the? ammeter an ammeter must be connected in the circuit in such a way that? all current flows through it ghe unit of measuring circuit resistance is the? ohm ohm's law is used tobdetermine relationships between voltage, current, and resistance which of the following are used to measure electrical resistance?
megohmmeter and ohmmeter when property of a material is present in every electrical circuit? resistance resistors are connected to electrical circuits to? limit current resistors connected in series across a voltage source to obtain a lower voltage are called voltage? dividers opposition to any voltage change in a circuit is caused by? capacitance what is the basic unit for measuring the capacitance of a capacitor? farad
magnetic fields which of the following materials are most commonly used for electrical conductors? aluminum and copper a material which has few free electrons, and therefore is a poor conductor, is called a? insulator what are insulating materials sometimes called? dielectrics as the current in a conductor increases, the heat it generates in the conductor increases? as the square of the current increase
what is the definition of a circular mil? the standard unit of measurement for wire cross-sectional areas dielectric strength is usually expressed in terms of? volts in simplified terms, what does ohms law state? the higher the resistance in the conductor, the more current in the line for the same voltage desirable characteristics of conductor insulation include? flexibility and mechanical strength a channel that holds and protects wirs or cables is known as a? race way BX cable has the same general characteristics as?
current how many paths for current will there be in a 50-volt circuit having five resistors in parallel? five if one leg of a parallrl circuit develops an open, the total current will? decrease what is common to all components of a parsllel circuit? voltage when the path of a circuit is broken, the circuit is called a? open circuit what device is used to interrupt current flow when a circuit develops a short circuit condition?
fuse in a y connected load or source line voltage is found by what formula? EL = √3Ep the formula for finding line current is a Y connected load or source is IL = 2 Ip in a Delta connected load or source the line voltage is found by what formula? EL = Ep the formula for finding the line current in a Delta connected load or sources IL = √3Lp
measuring the power of a 3-phase circuit at 50% power factor using only to 2 watt meter, 1 wattmeters will read zero power to which transformers wending is voltage supplied primary switch transformer winning is load connected secondary a transformer has 400 turns in the primary and 200 turn to the secondary at 240 volts are applied to the primary winding what voltage will be measured on the second winding 120 volts the volt amperes of the primary winding and the volt-amperes of the secondary winding in a transformer are equal
the output of capacity of a transformers is rated in KVA transformers losses are classified as copper losses and cross losses transformers core eddy current losses are reduced by using a laminated core what voltage will appear across the secondary terminals of an autotransformer if the common winding should open primary a variable transformer is a continuously adjustable Auto transformer
