# Page 1 MEGA = 1000000 KILO = 1000 MILLI = 0.001 ```T5
Electrical principles, math for electronics, electronic principles, Ohm’s Law
[4 Exam Questions - 4 Groups] Chapter 3A
Electrical Terms
Voltage is the electromotive force (EMF) that causes electron flow
The volt is the basic unit of electromotive force (EMF)
Electrical current is measured in Amperes
Current is the flow of electrons in an electric circuit
Direct Current flows only in one direction?
Alternating Current reverses direction on a regular basis
Electrical power is measured in Watts
Power describes the rate at which electrical energy is used
Copper is a good electrical conductor
Glass is a good electrical insulator
A mobile transceiver usually requires 12 volts
Electrical Units
Hertz is the unit of frequency
Capacitance is the ability to store energy in an electric field
Farad is the basic unit of capacitance
Inductance is the ability to store energy in a magnetic field
The Henry is the basic unit of inductance
RF is the abbreviation that refers to radio frequency signals of all types
Radio waves is electromagnetic waves that travel through space
Math Units
MEGA = 1,000,000
Million
KILO =
Thousand
1,000
MILLI =
0.001
1/1,000
MICRO =
0.000,001
1/1,000,000
PICO =
0.000,000,000,001
1/1,000,000,000,000
Decibel (dB)
+3 dB = 2X
-3 dB = X/2
+6 dB = 4X
-6 dB = X/4
+10dB = 10X
Ohm’s Law
E = I x R
Voltage = Current x Resistance
I = E / R
Current = Voltage / Resistance
R = E / I
Resistance = Voltage / Current
P = E x I
Power = Voltage x Current
I = P / E
Current = Power / Voltage
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