Electronics Flashcards
Electricity is
the flow of tiny particles called electrons
electric charge
is a quantity of electricity that is related to the
balance of electrons and protons in an object.
3 basic kinds of particles that make up atoms
protons, electrons, neutrons
imbalance of charges produces
static electricity
Electric charge affects
the way that objects interact
the Coulomb force
The electric force that one charged particle produces on another is called
Coulomb force is name after
Charles-Augustin de Coulomb.
which material is always electrically conductive
metals
speed of light
186,000 miles per second
an example of a conductor and an insulator
- silver, copper, gold
* rubber, oil, glass
what is a circuit
a never-ending looped pathway for
charge carriers
what happens when you cause a discontinuity in a circuit?
will prevent charge flow throughout the entire circuit
voltage
the measure of work required to move a unit charge from one location to another, against the force which tries to keep electric charges balanced.
voltage (in the context of circuits)
voltage is the amount of potential energy available (work to be done) per unit charge, to move charges through a conductor
electric current
flow of electric charge in a circuit
the rate of charge flow past a given point in an electric circuit
unit of electric charge
ampere
watts
rate at which an electrical device is converting energy from one form into another
currents flow… things and voltages are applied… things
through, across
always refer to the voltage between two points or
across two points in a circuit. Always refer to current through a device or connection in a circuit.
how are voltages generated?
by doing work on charges in devices
we get currents by
placing voltages across things
can use…. to measure current
a multi-meter
repeatedly changes its direction of current
alternating current
alternating current is caused by
voltages at the terminals swing from positive to
negative and back
always flows in the same direction, from positive to negative
direct current
Kirchoff’s Law states what about voltage
the sum of all voltage drops within a closed
circuit are equal to zero.
Kirchoff’s current law states
that there is a conservation of charge within a circuit,
this means that the sum of the current at a particular point (or component/node) are equal to the currents exiting that point.
resistance is measured in
ohms
resistance is
the opposition to the flow of current
ohms law descirbes
the proportional relationship between voltage and
current,
Resistors function by
dissipating power as heat
what are capacitors used for?
waveform, generation, filtering, and blocking and bypass applications
the most common uses of capacitors,
bypass and coupling
is the current proportional to voltage in a capacitor?
no
how do capacitors combine in parallel and series compared to resistors?
capacitors in series combine in the
same way as resistors in parallel, conversely
capacitors in parallel combine like resistors in
series
Inductance (L) can be defined as
the property where a conductor exhibits opposition to the change of electric current flowing through it.
what is inductance measured in?
henry (H)
the inductance of an inductor depends on…
its the physical properties and construction.
inductance may be increased by
reducing the length of the coil, increasing
the cross sectional area (A), increasing the number of
turns in the coil (N), and by using a core with a high level of permeability (μ)
dialetric means…
material will polarize when in contact with an electric field
What is the difference between
an Inductor and Capacitor?
- Capacitor stores energy in form of an Electric Field and an Inductor stores energy in form of a Magnetic field
- Capacitor tries to level the voltage in a circuit / and if the current changes, an inductor will charge or
discharge to equalize the current through the circuit.
impedance is
the sum of resistance, capacitive reactance, and inductive reactance
Impedance (Z) is the measure of the total opposition to current flow in an alternating current circuit.
