Transcript Electricity from Magnetism

Test over Magnetism- Friday
Agenda for the day
• Lecture- Magnetic Induction
• Finish Lab from yesterday…
Making an electromagnet…turn in
Finish coloring magnetsphere…turn in
Question of the day
If you can make a magnet from electricity,
can you also make electricity from a
magnet?
Michael Faraday
• It was largely due to his
efforts
that electricity became
practical for use in
technology. His efforts
created the “ancestor” of
the electric motor and
generators.
• Discovered
electromagnetic
induction (1831) ….which
was a turning point in
physics
Electricity from Magnetism
Current is induced by changing the
magnetic field
• Consider that there is no power source, but if
you move the magnet or move the
wire…current in created
REVIEW
• Which moves to create
current? The wire or
the magnet?
Does this mean we get something
(energy) for nothing?
• The law of conservation of energy states that
the Force times the distance traveled = Work
done…
• Work input = work output (or energy stored)
What can you do to create more
current?
Faraday’s Law
1) Increase the # of loops
2) Make the magnet or wires move faster
“The Great Revolution”…Einstein
• http://www.youtube.com/watch?v=TEVEBzNS
wTU
• And part 2