MODULE2 - DC CIRCUITS Flashcards
Learn fundamentals of DC circuits
Smallest amount of electrical charge having the quality called negative polarity
ELECTRONS
(T/F) Protons orbit the center of atoms
FALSE
a basic particle with positive polarity
PROTON
Protons are located in the _____ of atoms along with neutrons, particles which have neutral polarity
NUCLEUS
Electrical classification of all materials
CONDUCTORS, INSULATORS, SEMICONDUCTORS
Materials in which electrons can move freely from atom to atom
CONDUCTORS
CONDUCTORS have __ valence electron/s
1
The purpose of conductors is to allow electrical current to flow with ________
minimum resistance
(T/F) In general all metals are good conductors.
TRUE
Have 8 valence electrons
INSULATORS
Materials in which electrons tend to stay put and do not flow easily from atom to atom are termed
INSULATORS
(T/F) Insulators are used to prevent the flow of electricity.
TRUE
are used in components like capacitors which must store electric charges
DIELECTRICS
examples of dielectrics
glass, rubber, plastics
SEMICONDUCTORS have ___ valence electrons
4
Materials which are neither conductors nor insulators
SEMICONDUCTORS
Used in components like transistors
SEMICONDUCTOR
Example of semiconductor
CARBON, GERMANIUM, SILICON
The symbol for charge is Q which stands for ____
QUANTITY
The practical unit of charge is called the
COULOMB
One coulomb is equal to the amount of charge of ___ electrons or protons stored in a dielectric
6.25X10^18
The fundamental electric quantity
CHARGE
The smallest amount of charge that exists is carried by
ELECTRON AND PROTON
Atoms are composed of charge carrying particles: electrons and protons, and neutral particles, ____.
NEUTRONS
CHARGE OF PROTON
qp = 1.602x10^-19 C
Charge of an electron
qe = -1.602x10^-19 C
(T/F) In semiconductors - free electrons can be forced to move with relative ease, since they require little work to be moved.
FALSE
Charge in motion
CURRENT
(T/F) The more electrons in motion the greater the current
TRUE
When a charge is forced to move because of a ____ current is produced
POTENTIAL DIFFERENCE/VOLTAGE
indicates the intensity of the electricity in motion
CURRENT
The symbol for current is I which means
INTENSITY
Current is measured in
AMPERES
The definition of current is:
I = Q/T
1 ampere is
1 coulomb per second
Current moves through a circuit element
“THROUGH VARIABLE”
____ is rate of flow of negatively-charged particles, called electrons, through a predetermined cross-sectional area in a conductor.
CURRENT
refers to the the possibility of doing work
POTENTIAL
Any charge has the potential to do the work of attracting a similar charge or ____ an opposite charge.
REPULSING
The symbol for potential difference is E which means
ELECTROMOTIVE FORCE
The practical unit of potential difference is
VOLT
is a measure of the amount of work required to move 1C of charge
1 VOLT
Potential difference across two terminals in a circuit _____
ACROSS VARIABLE
Each cell provides 1.5V
Three cells connected one after another, in series, would provide ___
4.5V
(T/F) If the cells are connected in parallel, the voltage stays the same, but now a larger current can be drawn.
TRUE
Opposition to the flow of current is termed
RESISTANCE
The fact that a wire can become hot from the flow of current is evidence of
RESISTANCE
Conductors have ___ resistance.
VERY LITTLE
Insulators have ____ of resistance.
LARGE AMOUNT
The practical unit of resistance is
OHM
ohm is designated by the Greek letter __
OMEGA
an electronic component designed specifically to provide resistance
RESISTOR
defined as a path for current flow
CIRCUIT
In applications requiring the use of current, electrical components are arranged in the form of a
CIRCUIT
An open circuit has
INFINITE RESISTANCE
where the energy of the source (battery) is carried by means of the current through the the various components.
CIRCUIT
The circuit components are the ____ - they determines how much current the source will produce.
LOAD RESISTANCE
The battery is the ____, since it provides the potential energy to be used.
SOURCE
The direction of electron flow in our circuit is from the ____ side of the battery, through the load resistance, back to the _____ side of the battery.
NEGATIVE, POSITIVE
Inside the battery, electrons move to the negative terminal due to ______, maintaining the potential across the leads.
CHEMICAL ACTION
Circuits that are powered by battery sources are termed
DIRECT CURRENT CIRCUITS
In DC circuits, the battery maintains the ____ of output voltage. The plus and minus sides remain constant.
SAME POLARITY