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Stir - Stir
just a little misconception we have about electricity
"There has been confusion about the direction of flow of electricity in an electrical circuit
for more than 200 years. During the late 1700s, when it was discovered that electricity had a
polarity (+ and -), scientists such as Benjamin Franklin proposed that electricity flowed from
positive potentials to negative potentials. Thus during the development of electrical power
systems and rail systems during the 1800s electrical devices were marked with arrows to show
the direction electrical current is flowing from positive to negative in the devices and systems.
Around 1900 negatively charged electrons were discovered to be the actual source of electrical
current flow and they flowed from negative potentials and were attracted to positive potentials.
However, there was so much electrical equipment already in the world by 1900 marked with the
wrong direction of current flow and so many electricians that were taught about current that way,
the marking system has been continued to this day to be in the old, wrong direction. Even today
electrical and electronic devices such as diodes and transistors and their symbols are marked with
arrows in the opposite direction of electron current flow! This is one of the confusing problems
we face when we study electrical engineering today. "
see - you could be right Alex
geoff
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