Electromagnetic Induction & Alternating Current Resources: Grob: Basic Electronics Textbook: Chapters 15&16 http://www.sayedsaad.com/fundmental/3_Basic%20AC%20Generation.htm http://www.coolmagnetman.com/magindex.htm http://micro.magnet.fsu.edu/electromag/java/index.html http://www.regentsprep.org/Regents/physics/phys03/dinduction/default.htm

Michael Faraday While Orsted discovered a relationship between magnetism and electricity, Faraday discovered the principle of electromagnetism: that electricity can be created using magnetism. Faraday presenting to the Royal Society

Faraday’s Experiments http://micro.magnet.fsu.edu/electromag/java/index.html Show two of Faraday’s experiments

Left-Hand: 3 Finger Rule The direction that induced current flows depends upon the direction the flux lines cut across the conductor This direction can be determined by using the 3-finger rule. Pointing finger points from N to S pole. Thumb points in the direction in which the conductor moves. Middle finger indicates the direction of electron flow.

Alternating Current http://micro.magnet.fsu.edu/electromag/java/index.html

How it works!

Alternating Current cont.

AC vs DC (war of currents) Alternating Current Nikola Tesla (Westinghouse) Can be generated easily Can be sent long distances with little loss in power Does not require batteries Can be changed into DC easily when needed Few generating stations Direct Current Thomas Edison Can be generated easily Difficult to send long distances Most devices need DC Sometimes requires the need for batteries Many generating substations (less than mile)

Sine Wave

Volts/Div= ______________ Sec / Div = ______________ Period (Time) = __________ Frequency= ____________ Peak V = ________ P-P Voltage = _________ RMS V= _________