DC stands for "direct current" the one-way movement of charges in a
circuit, around and around. There is a distinct positive and negative
in DC circuits.
AC stands for "alternating current," the oscillating movement of
charges, back and forth in a c...
Ohm (R or o or Ω) is the unit of electrical resistance. It is
resistance to the flow of charges in a circuit, like friction that
slows down a motor belt.
Ohm's Law states the relationship between volts, amps,and ohms. It
can be presented in three wa...
The Power Equation states the relationship between volts, amps, and
watts. It can be presented in three ways:
Volts x Amps = Watts
Watts ÷ Amps = Volts
Watts ÷ Volts = Amps
Example: A lightbulb running at 120 volts and drawing 1
amp is using ener...
Wattage (W or P) is the rate of energy flow. Two things move in
electrical circuits--charges and energy. Charges move slowly around or
back and forth in a circuit, never leaving.Energy moves almost
instantaneously from generating source to load, changi...
Watt-hours (WH or Wh; KWH or kWh) describes accumulated energy. If a
turbine generates at the rate of 100 watts for one hour, it will have
generated 100 watt-hours. This is the same sort of measure as joules.
Energy, which is measured in watt-hours, is a ...
Amp-hours (AH or Ah) are the units of accumulated or cycled charge.
It's the same type of measurement as coulombs. This is a quantity of
"stuff," but it's not "used up," it just moves around in a circuit. We
also talk about battery capacity in terms of am...
Amperage (A or I) is the rate of charge flow. Charges (electrons, in
wires) move around or back and forth in a circuit at a certain rate,
and the amp is the unit measurement. It's also known as amperes, amps,
intensity, electrical current, and coulombs pe...
Power factor is the ratio of true power or watts to apparent power or
volt amps. They are identical only when current and voltage are in
phase than the power factor is 1.0. The power in an ac circuit is very
seldom equal to the direct product of the vo...
Voltage (V or E) can be thought of as electrical "pressure." It's the
push that moves electrons, and hence energy, through wires. Voltage is
not an indication of energy capacity. You can have the same voltage in
a tiny blood vessel and a huge viaduct, whi...
