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About Electricity
5. What did people do in electricity research?
6. Unit of Electricity
7. Application of Electricity
8. What is Triboelectrification?
Q: What did people do in electricity research after Miletus’ discovery?
A: Dating back to the 18th century, Benjamin Franklin, a famous American scientist,
proved that lightning was caused by electricity by describing an experiment in which
an electrical conductor would be used to extract power from a thundercloud. In the
experiment, he flew a kite with a metal key attached to it into a suitable cloud. The precise
historical details are unclear, but he may have then retrieved the key and discharged
electricity from it. By using the principles, he successfully invented the lightning rod. In 1799,
the Italian scientist Alessandro Volta went on to create a “voltaic pile”
consisting of alternating layers of copper and zinc separated by paper
soaked in salt water. This generated a larger current and is credited
as the first battery. In 1821, the English scientist Michael Faraday
created the world’s first electric motor, even though it was very
simple. All the motors that we use today are based on that design.
Ten years later, Faraday made another contribution to the world with
his second crucial invention, the dynamo. In 1866, the first industrial
dynamo was invented by a German named Siemens.
Q: What is the unit for electricity?
A:
Electricity has various related units of measure. Electrical current
flow is measured in Amperes (Amps), which is named in honor of
the famous French physician André-Marie Ampère and the
contribution that he made. Electrical resistance is measured
in Ohms, which is named after the German physicist
George Ohm for his contributions. Electrical force, or the
electrical difference of potential that would drive one
ampere of current against one ohm of resistance, is
measured in Volts, which is named after the Italian
physicist Alessandro Volta for his contributions.
Electrical power is measured in Watts, which is
named after the famous Scottish inventor James
Watt for his contributions.
Q: All the home appliances don’t work when a blackout
happens. It is very inconvenient without electricity in life.
A: Absolutely! We need electricity
a lot because it can either be
used for cooking, watching TV, or
transportation.
Q: I found it very interesting that a plastic ruler cannot
attract any bits of paper, but when it is rubbed against hair
several times it does.
A: Yes, that’s it! This is the phenomenon
of Triboelectrification. Rubbing glass with
fur, or a comb through your hair, can build
up triboelectricity. Most everyday static
electricity is triboelectric. The polarity and
strength of the charges produced differ
according to the materials, surface
roughness, temperature, strain, and other
properties.
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