ch 12345
What part of an atom has a negative charge ?
electron
Electrical current is the flow of __________.
electrons
The number of cycles completed in one second is called a
frequency
The neutral conductor is also referred to the __________ conductor.
grounded
A complete circuit is often referred to as a(n) ___________ circuit.
closed
There are six current-carrying conductors in a raceway that is to be installed in an area with an ambient temperature of 90 degrees F. It is necessary to __
correct for temperature and derate because of the number of conductors
In series circuits, the ____________ is the same at any point in the circuit.
current
The term "load" refers to the amount of __________ in a branch circuit.
current
When a circuit has only one path, the __________is the same at any point.
current
Parallel circuits are also referred to as ___________
current dividers
The unit circular mil is equal to the ______
diameter of the wire in mils
What type of current reverses its direction of flow at regular intervals ?
direct alternating
What are the three principle parts of an atom ?
electron, neutron, and proton
In a series circuit, the sum of the voltage drops is ____________ the applied voltage.
equal to
Both AC and DC can be transformed
fals
All insulations perform equally well in dry, damp, and wet locations.
false
During normal operation of a typical 120-volt appliance circuit, current flows through the hot, grounding, and neutral conductors.
false
1/1 Frequency is measured in _____________
hertz
The longer the conductor, the more _____________ it will have.
resistance
What is indicated by the fourth color band on a resistor?
tolerance
A grounding conductor helps prevent a shock hazard in the event that an ungrounded, or hot, conductor comes in contact with the case or frame of an appliance.
true
The value of a resistor can often be determined by the color code.
true
Direct current is described as
unidrectional
What force pushes the electrons through a resistance in a circuit?
voltage
What is another term for electromotive force (EMF)?
voltage
The amount of electrical power being used in a circuit is measured in _____________.
watts
If a circuit is open, current ____________ flow.
will not
A series circuit has a total resistance of 180 ohms and a applied voltage of 120 V. What is the current flow?
.667
A parallel circuit composed of a 150 ohm and a 270 ohm resistor has a voltage of 120V. What is the current in the 150 ohm resistor?
.8A
A conductor is made from a material that contains between ________ valence electrons.
1 and 3
A two branch parallel circuit has resistors of 30 ohms and a 15 ohm resistor. What is the total resistance?
10
An electrical circuit has a voltage of 50V and a resistance of 5 ohms. What is the value of current?
10A
A three resistor circuit has a total power of 25W. Two of the resistors dissipate 10W and 5W, respectively. How much power does the third resistor dissipate?
10w
An electric circuit has a resistance of 20 ohms. The current is measured to be 6 A. How many volts are applied to the circuit?
120
A toaster is listed as 1560 W. When it is plugged into a 120 V circuit and starts to make toast, how many amperes will it draw?
13
A three branch parallel circuit has a total resistance of 385.83 ohms, Two of the resistors are 680 ohms and 1500 ohms. What is the value of the third resistor?
2200
If there are more than _________ conductors in a raceway, the ampacity of the conductors must be derated.
3
A parallel circuit is composed of two 60 ohm resistors. What is the total resistance?
30
The ampacities listed in T.310.15(B)(16) are based on an ambient temperature of ________________.
30 degree F
The NEC ___________ contains tables dealing with conductors for general wiring.
310
An electric motor is running on 120V. The current is measured to be 2 A. How many ohms of resistance is the motor?
60
A two resistor series circuit has an applied voltage of 100V. The voltage across one of the resistors is 40V. What is the voltage across the other resistor?
600v
An insulator is a material containing _________ valence electrons.
7 or 8
A three branch parallel circuit has resistors of 27 ohms, 56 ohms, and 15 ohms. What is the total resistance?
8.23
What is the applied voltage in a series circuit with two resistors (25V and 60 V respectively)?
85v
A series circuit has a total resistance of 240 ohms and a current flow of 4 A. What is the applied voltage?
960V
In the NEC the current carrying abilities of conductors are called the ______________.
ampacities
In parallel circuits, the voltage drop across any branch is the same as the
applied voltage
A basic laws of magnetism states that unlike poles ________ and like poles ____________
attract, repel
A combination circuit is a circuit that contains ___________.
bothe series and parallel components
In a parallel circuit, the total resistance is __________ value resistor.
less than the lowest
What is the most common method of producing electricity ?
magnetism
A method for finding total resistance of parallel resistors is _____________.
resistors of equal value product over sum reciprocal formula (all of these)
A circuit that has only one path for current flow is a ___________ circuit.
series
There is very little resistance and a large amount of current flow in a(n) ___________ circuit.
short
What type of circuit generally occurs when the conductors leading from and back to the power source become connected ?
short
In a parallel circuit, the total current flow is equal to the ___________ of the currents through all the branches.
sum
The ambient air temperature considered in relation to a conductor ampacity is the temperature of the _______
surrounding air
When a conductor is very large it may become necessary to connect them in
parrallel
What part of an atom has a positive charge ?
proton
Solving combination circuits includes a step in which you
recuce the circuit to asimpler circuit
The basic law of physics states that like charges __________ and opposite charges __________.
repel ; attract
What force is demonstrated in objects with like charges
repulsion
What force is demonstrated in objects with unlike charges ?
repulsion
Circuits that have more than one path for current flow are ___________ circuits. (1pts)
parallel
A voltage ____________ is used to provide different voltages between certain points in a circuit.
divider
What standard prefix in engineering notation indicates multiplication by 1,000?
mega
What part of an atom has no charge ?
neutron
A junction point of current paths is often called a __________.
node
The unit of resistance to current flow is the ____________.
ohm
