Flashcards in ITEC 220 Test #1 Deck (69):
1
Short circuit
An unintended path for current to flow which bypasses the intended devices
2
A three-wire line cord has one connector tied to chassis ground
True
3
Fuse
A protection device which overcurrent produces heat to melt a fusible element
4
Circuit breaker
A circuit interruption device that activates when an overcurrent is applied
5
Thermal overload
A protection device that opens when the ambient temperature rises above the rated value
6
Electromechanical relay
A switch that is activated by electromagnetism
7
If a fuse blows, replace it with a higher valued one
False
8
A fuse is what type of indicator
Circuit overload
9
An interlock or third-wire ground plug is an example of
Prevention protection
10
Schematic symbol
Drawings that represent components
11
Transducer
A device that changes one from of energy into another form
12
Atom
The smallest particle of an element
13
Proton
A heavy positive particle in the nucleus of an atom
14
Electron
A light negative particle orbiting the nucleus of an atom
15
Nucleus
The center of an atom. It consists of protons and neutrons
16
Neutron
A heavy particle, having no charge, found in the nucleus of an atom
17
Charge
The attraction and repulsion between particles
18
Element
A material that cannot be broken down by chemical reaction
19
Molecule
The smallest unit of a compound that has the same characteristics as the compound
20
Compound
A material whose molecules are the same
21
Shells/rings
The layers in which the electrons are found
22
The smallest particles into which an atom can be divided are called
Protons and electrons
23
An electron has a negative charge
True
24
Unlike charges repel each other
False
25
What is formed when two or more atoms of different elements are combined
A molecule
26
Valence electrons
The outermost electrons of an atom
27
Free electrons
Valence electrons that can move easily from atom to atom
28
Insulators
Compounds in which the bonding of the atoms prevent the valence electrons from becoming free electrons
29
Dielectrics
Insulators that help electrodes store charge
30
Conductor
Material whose atoms on the outer ring are less than half complete
31
Semiconductor
Element whose outer ring is half of electrons is exactly half complete
32
Resistance
The opposition to the movement of electrons in a conductive material
33
Ohm
The unit of electrical resistance (a current of 1 amp will flow when there is a potential difference of 1 volt across it.)
34
Mil
One-thousandth of an inch
35
Circular mils
Equal the square of the diameter expressed in mils
36
How many electrons are in the outer ring of atoms of semiconductor material
4 electrons
37
A conductor has (few,many) free electrons
Few
38
Static electricity
Refers to the electrical charge generated by friction
39
Coulomb
A unit of charge equal to the charge produced by 6.24 x 10 to the eighteenth
40
Potential difference
Difference between points A and B is the potential of B subtracted by A.
41
Volt
A unit of potential difference (can move 1 coulomb of charge while producing 1 unit of electrical work)
42
Joule
The unit of work energy
43
Electromotive force
The potential difference between the terminals of a device which can be a source of electrical energy
44
Current
The movement of electrical charge
45
Ampere
The unit of current
46
Conductance
The ability of a circuit to move electrical charges
47
Watt
The expenditure of one joule of energy in one second of time
48
What is the basic unit used to describe a difference of potential
Volt
49
Current defines a quantity of flow of electrons
True
50
Electrode
Electrical conductor by which current enters or leaves a medium such as an electrolyte.
51
Electrolyte
Any solution that conducts electric current
52
Anode
The negative terminal of a primary cell. The terminal where oxidation takes place
53
Cathode
The positive terminal of a primary cell
54
Battery
A voltage source which is usually a combination of electrochemical cells
55
Wet cell
Cell that has liquid electrolytes
56
Dry cell
Cell having the electrolyte in the form of a moist paste
57
Primary cell
A cell that converts chemical energy to electrical energy by an irreversible chemical reaction
58
Secondary cell
A cell that converts chemical energy into electrical energy, but the cell can be recharged
59
Five methods of generating voltage
Mechanical, chemical, static, thermal, and light
60
Why is a voltaic cell impractical to use
Because the charges have reached a state of equilibrium
61
What method of generating electricity is most widely used for home lighting and appliances
Mechanical
62
Piezoelectric effect
An effect in which electric polarization is produced by mechanical pressure
63
Thermocouple
A device consisting of two metals, one whose junction is kept at a fixed temp
64
What determines the amount of voltage generated by a solar cell
The intensity of the sun
65
What could a solar cell be used for
Satellites
66
What determines the amount of current generated by a thermocouple
Intensity of the heat applied
67
Possible applications of a thermocouple
Temperature control and monitoring inudstrial processes
68
What is piezoelectricity
Mechanical pressure of crystals that create an electrical charge
69