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Reminder:. Exam next Friday!!. April 11 Bring a pencil and a calculator! Cheat sheet is up now … HW8 due on Wednesday. Electric power generation. (Motional EMF). uniform. uniform. uniform. Click for animation!. uniform. uniform. Motional EMF.
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Reminder: Exam next Friday!! April 11 Bring a pencil and a calculator! Cheat sheet is up now … HW8 due on Wednesday
Electric power generation (Motional EMF)
uniform Click for animation!
Motional EMF What’s the EMF and direction of current flow?
Now, look at this another way! (microscopic)
uniform q
SUMMARY Macroscopic point of view: From Faraday’s law, we concluded that the moving bar develops an EMF: Microscopic point of view: Considering the force on an individual charge carrier inside the bar, we also concluded that the bar develops an EMF:
Net forces on conductors? Do you get something for nothing? i.e. how do you keep bar moving?
Number example! What external force is required?
External Power supplied? Internal Power dissipated? Note Lenz’s Law at work -- you have to supply external power to make electrical power! Eddy current demo
Let’s make an AC generator (Alternator) N S Click for animation!
Let’s make an AC generator (Alternator) N S Generator sim http://phet.colorado.edu/en/simulation/generator
Wall current: 120 VRMS at 60 Hz: Suppose you have A = 0.5 m2 and B = 0.1 T. How many turns do you have to have?