In the same sense, electrical pressure - just as
water pressure pushes water through a pipe. Voltage, causes CURRENT to
flow through a wire.
VOLTAGE has several other names. It is sometimes
called ELECTROMOTIVE FORCE (E.M.F. for
short), IR DROP (this will be explained a
little later), and POTENTIAL DIFFERENCE.
The unit of measurement for VOLTAGE is the VOLT, and it is measured by a VOLTMETER. You may run into KiloVolts (Thousand
Volts), MilliVolts (1 Thousandth of a Volt), or even MicroVolts (1
Millionth of a Volt).
The problem with discussing VOLTAGE is that it is difficult to talk
about it, without discussing CURRENT and RESISTANCE at
the same time.
The three are almost inseparable. CURRENT is the
term used to describe the FLOW or movement of
electrons. Water has current. Electricity has current. Water has
current only when the river flows. If it is standing water, such as in a
pond, it does not flow, and therefore has no current. Electricity only has
current when it is on the move. Current is measured in AMPEREs, using an AMMETER,
typically using MilliAmperes or MicroAmperes. |