1. PHYS 270 – SUPPL. #7 DENNIS PAPADOPOULOS FEBRUARY 17, 2010 1

2. Electromagnetic Induction Topics: Induced Currents X Motional emf X Magnetic Flux X Lenz’s Law X Faraday’s Law X Induced Fields X Induced Currents Applications –Generators –Transformers –Inductors –LC and LR Circuits

5. FARADAY’s LAW 5

6. AC GENERATORS 6

7. EDDY CURRENTS Induced current in complete loop Causes retarding force on wire 7 What happens if I have no wires to define current path in a metal sheet. Two whirlpools of current circulate.

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9. 9 Transformers principle

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15. Induced E field is directly connected to a changing magnetic field

18. INDUCTORS VS. CAPACITORS

20. Inductors - Inductance Define the Self Inductance L as the proportionality constant in Units ? For infinite solenoid

21. CALCULATION OF INDUCTANCE OF A SOLENOID