Slides Flashcards
All matter is composed of ____.
atoms
What is at the center of the atom?
Nucleus
Proton’s are ____ charged.
positively
Neutron’s are ____ charged.
neutral (no charge)
Electron’s are ____ charged.
negatively
Orbits the nucleus in energy levels or shells
Electron
Atoms lose or gain electrons which causes an imbalance in charge.
Atoms become either positively or negatively charged and are then called?
positive ions
negative ions
Valence electrons are at the ____ level from the nucleus
farthest
The electron can escape the magnetic pull of the
nucleus and become a…?
free electron
Made of materials that easily allow electrons to flow.
– Silver, copper, and gold
- Contains many free electrons
– Move easily from atom to atom
– Contain heat energy which can cause movement
- Electron movement
–Relative to the resistance (movement opposition) the conductor presents
– Also called electric current
Conductor
Made of materials that inhibit the flow of electrons
– Glass, rubber, and plastic
Few free electrons
Insulator
Made of materials that are neither good as a conductor nor as an insulator
– Silicon and Germanium
Semiconductor
The electrical energy/force required to move electrons from one place to another
ex. Chemical reaction inside a battery
Voltage
Voltage is also sometimes referred to as?
The potential or the difference of potential
EMF – ElectroMotive Force
Voltage Symbol
E or V
Voltage Unit of Measurement
Volt
Voltage symbol for unit of measurement
V
Movement of free electrons through a conductor
Current
Rate of movement measured in amperes
– Amount of electric charge passing a point in time
Current
Symbol for Current
I
Current Unit of Measurement
Ampere
Current Symbol for Unit of Measurement
A
The amount of opposition a device or material offers against electrons/current movement
Resistance
Symbol for resistance
R
Resistance Unit of Measurement
Ohm
Resistance symbol for unit of measurement
Ω
The ability of materials to pass electrons
Opposite of resistance
Conductance
Inductance is the physical property of a circuit that opposes changes in current flow.
Inductance
An inductor, also called a coil, choke, or reactor, is a two-terminal electrical component that stores energy in a magnetic field when electric current flows through it.
Inductor
The symbol for an inductance is
L
Inductance is measured in…?
henries (H)
A _____ is a device that stores electrical energy in an electrostatic (electric) field.
capacitor
The effect of a capacitor is known as _____.
capacitance
______ is the ratio of the change in electric charge of a system, to the corresponding change in its electric potential.
capacitance
Capacitance (C) is measured in…?
farads (F)
Today, ______ are widely used in electronic circuits for blocking direct current while allowing alternating current to pass.
capacitors
The following picture is the symbol for what kind of capacitor?
Adjustable Cap
The following picture is the symbol for what kind of capacitor?
Electrolytic Cap
The following picture is the symbol for what kind of capacitor?
Standard Cap
Capacitors in analog filter networks, they do what?
smooth the output of power supplies.
Capacitors in resonant circuits, they do what?
tune radios to particular frequencies.
Capacitors in electric power transmission systems, they…?
stabilize voltage and power flow.
Rate of doing work (how fast energy is used)
The measure of how much energy is converted to heat
Represented by P and W
P = symbol for ____
Watt = unit of measurement
W = symbol for unit of measurement
Power
- The amount of current in a circuit is directly proportional to the amount of applied voltage and inversely proportional to the amount of circuit resistance
- Applied to circuit configurations to calculate voltage, current and resistance
Ohm’s Law
Current is affected by voltage and resistance -
If resistance decreases – current ____ (voltage is unchanged)
increases
Current is affected by voltage and resistance -
If resistance increases – current _____ (voltage isunchanged)
decreases
Current is affected by voltage and resistance -
If voltage increases – current increases IF…?
resistance is unchanged
According to Ohm’s Law, how do you solve for current?
According to Ohm’s Law, how do you solve for voltage?
According to Ohm’s Law, how do you solve for resistance?
Ohm’s Law formulas may be easier to remember using the VIR circle. In the VIR circle, voltage is always…?
On top
Mandatory devices for a simple circuit:
Power supply (battery)
Load device (resistance)
Conductor (wire; continuity)
An electrical component that draws current from a voltage source
All load devices have a certain amount of resistance (load resistance)
Load Device
Optional devices for circuit configurations:
Protective device (fuse or circuit breaker)
Control device (switch)
Monitoring device (meter)
There are two two basic circuits:
Series
Parallel
The following describes which kind of circuit?
- Current flows in a single path through every component in the circuit
- Simplest of all circuits
If circuit has one resistor, total resistance is equal to the value of that resistor. - If the circuit has more than one resistor the values of all the resistors must be added together before you calculate current.
- Current has only one path – from the negative side of the power source to the positive side
- Current is the same at every point in the circuit
Series
The following describes which kind of circuit?
- Current has more than one path (branches) to follow
- Each branch is connected across the same voltage source
Parallel
Kirchhoff’s Laws are used to find ____ like unknowns in a circuit
multiple
Kirchhoff’s Laws – Series Circuits
Voltage – in any closed circuit, the applied voltage is ___ to the sum of all the voltage drops in the circuit
equal
Kirchhoff’s Laws – Series Circuits
Current –The sum of all currents flowing to a point must be equal to the ____ of all currents
sum
Kirchhoff’s Laws – Parallel Circuits
Voltage - Voltage is the ____ (common) across each branch (each branch is connected across the same voltage source)
same
Kirchhoff’s Laws – Parallel Circuits
Current - Current in each branch ____ on the resistance in the branch
depends
Series Formulas - Applied Voltage
EA = ER1 + ER2 + ER3
Series Formulas - Total Resistance
RT = R1 + R2 + R3
Series Formulas - Total Current
IT = IR1 = IR2 = IR3
Parallel Formulas - Applied Voltage
EA = ER1 = ER2 = ER3
Parallel Formulas - Total Current
IT = IR1 + IR2 + IR3
Parallel Formulas - Total Resistance
Product/Sum
Equal Value
Reciprocal
Parallel Formula - Total Resistance - Product/Sum
Parallel Formula - Total Resistance - Equal Value
Parallel Formula - Total Resistance - Reciprocal
The following is describing which Total Resistance formula?
- Beneficial with just two branches in a parallel circuit
- The two values are multiplied as a product above the same two values added together as a sum
Product Over Sum
Note that in a parallel circuit total resistance will always be ____ than the smallest branch resistance.
less
In a parallel circuit, if a branch is added total resistance will decrease and total current will _____.
increase
In a parallel circuit, if a branch is ____ total resistance will increase and total current will decrease.
removed
The following describes which Total Resistance formula?
The total resistance of any number of equal value resistors connected in parallel is equal to the resistance of one resistor divided by the number of resistors
Equal Value
RF Career Field systems radios use ___ voltages to power internal components/circuits
DC
RF Career Field systems radios operate from ___ battery source or both
one
RF Career Field systems radios power up…?
memory circuits
RF Career Field systems radios ___ ___ retains radio settings
hub battery
The rate of doing work measured in watts
Power
The mathematical formula for calculating power for a series circuit and a parallel circuit is the ____.
same
The mathematical formula for finding power in a series circuit is?
Either add all the individual powers or use P = I * E if the current and voltage is known
The mathematical formula for finding power in a parallel circuit is?
Same as in series circuit
Either add all the individual powers or use P = I * E if the current and voltage is known
In a series circuit, if voltage remains constant and resistance
increases, current will ____.
decrease
In a series circuit, if voltage remains constant and resistance
decreases, current will ____.
increase
In a series circuit, if resistance remains constant and voltage
increases, current will ____.
increase
In a series circuit, if resistance remains constant and voltage
decreases, current will ____.
decrease
In a parallel circuit, If voltage remains constant and resistance
increases, current will ____.
decrease
In a parallel circuit, If voltage remains constant and resistance
decreases, current will ____.
increase
In a parallel circuit, if resistance remains constant and voltage
increases, current will _____.
increase
In a parallel circuit, If resistance remains constant and voltage
decreases, current will ____.
decrease
In a parallel circuit, If a branch is added, total resistance will
____ and total current will ____.
decrease
increase
Alternating Current (AC) is produced by a ____ (electromagnetic device)
generator
The ____ is coils of wires wrapped around a metal core
rotor
The ____ is a set of stationary magnets
stator
____ ____ is produced when the rotor turns (rotates) around the magnetic field of the stator
Electric current (AC)
The strength and direction of the current depends on the ____ and ____ of the rotor. This results in constantly changing amplitudes and different directions.
position and direction
One voltage waveform is called a sinewave, this is also called sinusoidal wave or sinusoid
sinusoidal wave or sinusoid
In a sine wave, the sine of the angle of rotation represents the amount of ___ ___.
induced voltage
Sine waves are analyzed by ____.
vectors
____ represent amplitude and phase relationships of voltage and current.
vectors
Maximum peak of a sine wave is ____ and minimum peak is ____.
max - 90 degrees
minimum - 270 degrees
The following describes which waveform?
Instantaneous rise and fall
Symmetrical
Square Wave
The following describes which waveform?
Instantaneous rise and fall
Asymmetrical
Rectangular Wave
The following describes which waveform?
Slow increase with a linear rate of change to peak value; then a rapid drop to maximum negative
Also called ramp voltage
Sawtooth Wave
AC sine waves have 3 primary voltage measurements:
Peak (VPK)
Peak-to-peak (VPK-PK)
RMS (Effective)
The following describes which voltage measurement?
The peak, or maximum, voltage of just one alternation of a sine wave
Peak (Epk or VPK)
The following describes which voltage measurement?
The voltage from the positive alternation to the negative alternation
Peak-to-Peak (VPK-PK)
The following describes which voltage measurement?
The effective voltage – amount of AC voltage that will do the same amount of work as DC voltage
RMS (Effective) - RMSEFF or VAC or VRMS or EFF
Root-Mean-Square
One cycle of AC has a ____ alternation and a _____ alternation – 2 halves
positive
negative
Frequency of an AC waveform is the number of cycles in a ____
second
Cycle is one complete ____ of AC
360 degree
Symbol for frequency is…?
f
____ unit measurement for frequency
Hertz (Hz)
The actual distance between the beginning and the end of one complete AC cycle
Wavelength
Symbol for wavelength is the Greek letter…?
Lambda (λ)
Wavelength is expressed in…?
Meters
The following describes which phase relationship?
Two sine waves of the same frequency pass through zero at the same time and reach positive peak together
In-phase
The following describes which phase relationship?
Two sine waves of the same frequency do not pass through zero at the same time and reach positive peak at different times
Out of phase
Frequencies between 0 Hz and 3KHz
Power Frequencies
Frequencies between 15 Hz and 20 KHz
High frequencies are the higher-pitch tones and may not be heard by everyone
Audio Frequencies
Frequencies between 20 KHz and 300 GHz
Transmits intelligence (audio) through space using electromagnetic waves
RF Frequencies
Frequencies between 1 GHz to 300 GHz
Microwave frequencies
Frequency between 3kHz – 30kHz
VLF – very low frequency
Frequency between 30kHz – 300kHz
LF – low frequency
Frequency between 300kHz – 3MHz
MF – medium frequency
Frequency between 3MHz – 30MHz
HF – high frequency
Frequency between 30MHz – 300MHz
VHF – very high frequency
Frequency between 300MHz – 3GHz
UHF – ultra high frequency
Frequency between 3GHz – 30GHz
SHF – super high frequency
Frequency between 30GHz – 300GHz
EHF – extremely high frequency
Range extends to around 10^17 Hz
Infrared, visible range, and ultraviolet
Optics
Range extends to around 10^23 Hz
x-ray
