CSLB contractor B exam (electrical)

CSLB contractor B exam (electri
vg vg vg vg



cal)
1.Electrical Circuit: An vg vg vg

consists of a power source, conduc- tors, and load
vg vg vg vg vg vg vg vg


2.simple curcuit: A vg vg vg

consists of only one energy source, one conductor, and one load.
vg vg vg vg vg vg vg vg vg vg


3.series curcuit: A simple vg vg vg vg




has at least two loads. The current flows along a single path and the
vg vg vg vg vg vg vg vg vg vg vg vg vg vg

components are located one after another along this path
vg vg vg vg vg vg vg vg


4.parallel curcuit: A simple vg , the voltage applied to each vg vg vg vg vg vg vg vg vg

branch is the same vg vg vg

5.direction of current: what do arrows indicatevg vg vg vg vg vg

6.electron flow: Inside a DC power source (such as a battery) the elec
vg vg vg vg vg vg vg vg vg vg vg vg

trons travel from the positive terminal to the negative. Electrons trav
vg vg vg vg vg vg vg vg vg vg

eling outside of the power source (a circuit) electrons travel from the
vg vg vg vg vg vg vg vg vg vg vg v

gnegative to the positive terminal. vg vg vg vg


7.continuity: The continuous effective contact with all parts of an elec
vg vg vg vg vg vg vg vg vg vg

trical circuit to give it a high conductance (low resistance).
vg vg vg vg vg vg vg vg vg

8.direct current and alternating current: What are two types of electric
vg vg vg vg vg vg vg vg vg vg vg

urrent?
9.power source: In any completed circuit, it takes a force to push the
vg vg vg vg vg vg vg vg vg vg vg vg v

gelectrons through the , conductor, and load. The two types of force
vg vg vg vg vg vg vg vg vg vg vg vg

to push the electrons of electric current are direct current (DC) and a
vg vg vg vg vg vg vg vg vg vg vg vg

lternating current(AC). vg

10.load: 1) Power output such as a power plant.
vg vg vg vg vg vg vg vg

(2)A device to which power is delivered.
vg vg vg vg vg vg

(3)The demand upon the operating resource of a system such as
vg vg vg vg vg vg vg vg vg vg vg

a telephone exchange system or circuit of garden lights.
vg vg vg vg vg vg vg vg


11.direct current: The polarity from vg vg vg vg vg




power sources never changes; that is, the current flows out of the ne
vg vg vg vg vg vg vg vg vg vg vg vg

gative terminal of the power source in the same direction
vg vg vg vg vg vg vg vg vg


12.alternating curent: power sources produce a voltage and current th
vg vg vg vg vg vg vg vg vg

at has a constant change in polarity and magnitude at a constant fre
vg vg vg vg vg vg vg vg vg vg vg vg

quency, back and forth in a conductor.
vg vg vg vg vg vg vg

flow is produced by a generator or an alternator.
vg vg vg vg vg vg vg vg

13.frequency: The rate of flow reversal is called vg vg vg vg vg vg vg

14.60 cycles per second (60 Hz): Nearly all AC power systems in U.S.A.
vg vg vg vg vg vg vg vg vg vg vg vg

operate at a frequency of
vg vg vg vg vg


15.AC waveforms: When an alternator produces AC voltage, the voltag
vg vg vg vg vg vg vg vg vg


1vg/
vg19

, CSLB contractor B exam (electri
vg vg vg vg



cal)
e switches polarity over time, but does so in a very particular manner.
vg vg vg vg vg vg vg vg vg vg vg vg

When graphed over time, the "wave" traced by this voltage of altern
vg vg vg vg vg vg vg vg vg vg vg vg

ating polarity from an alternator takes on a distinct shape, known as
vg vg vg vg vg vg vg vg vg vg vg v

a sine wave.
g vg vg


16.conductance: vg

is the property of metal that permits current to flow
vg vg vg vg vg vg vg vg vg

17.1/resistance: =conductance vg




2vg/
vg19

, CSLB contractor B exam (electri
vg vg vg vg



cal)
18.resistance: vg




is the opposite of conductance. It is the property that opposes the flow
vg vg vg vg vg vg vg vg vg vg vg vg

of electric current and the friction opposition to the flow of electrons
vg vg vg vg vg vg vg vg vg vg vg vg

19.impedance: vg




is the total opposition to current flow in an ac circuit,
vg vg vg vg vg vg vg vg vg vg

is measured in ohms
vg vg vg

20.voltage: Electron pressure is called electromotive force. The electro
vg vg vg vg vg vg vg vg

motive force literally means the force that moves electrons. The unit
vg vg vg vg vg vg vg vg vg vg vg

of measure of this force is the
vg vg vg vg vg vg vg


21.current: Free electrons moving in the same direction in a conductor
vg vg vg vg vg vg vg vg vg vg

produce an electrical
vg vg vg vg




sometimes called intensity (I). The rate at which electrons move is m vg vg vg vg vg vg vg vg vg vg vg

easured by the unit called ampere (A). vg vg vg vg vg vg

22.power: is defined as the rate at which work is done vg vg vg vg vg vg vg vg vg vg

23.watt: unit of power vg vg vg

24.I x E (Intensity of current in amps x Electromotive force in volts): for
vg vg vg vg vg vg vg vg vg vg vg vg vg

mula for power vg vg

25.P + E (Power in watts + Electromotive force in volts): amps formula
vg vg vg vg vg vg vg vg vg vg vg vg

26.P + I (Power in watts + Intensity of current in amps): volts formula
vg vg vg vg vg vg vg vg vg vg vg vg vg

27.directly: Current is proportional to voltage? vg vg vg vg vg

28.360 volts: For 208 volts x 1.732, use vg vg vg vg vg vg vg

29.398 volts: For 230 volts x 1.732, use volts vg vg vg vg vg vg vg vg

30.416 volts: For 240 volts x 1.732, use volts vg vg vg vg vg vg vg vg

31.762 volts: For 440 volts x 1.732, use volts vg vg vg vg vg vg vg vg

32.797 volts: For 460 volts x 1.732, use volts vg vg vg vg vg vg vg vg

33.831 volts: For 480 volts x 1.732, use volts vg vg vg vg vg vg vg vg

34.1000n: how do you write 1,000 ohms vg vg vg vg vg vg

35.power factor: Alternating— vg vg

Current circuits develop inductive and capacitive re- vg vg vg vg vg vg

actance, which causes some power to be stored temporarily in the el
vg vg vg vg vg vg vg vg vg vg vg vg

ectromagnetic field of the inductor or in the electrostatic field of the vg vg vg vg vg vg vg vg vg vg vg vg

capacitor.
36.True power (W) / vg vg vg

Apparent Power (VA) Watts / Volt-
vg vg vg vg vg vg

Ampere
esistance (R) / Impedance (Z): 3 formulas for power factor
vg vg vg vg vg vg vg vg vg



3vg/
vg19