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Can we solve the energy crisis? How do you use Lenz's Law?

posted May 2, 2018, 11:35 AM by Barbara Fortunato   [ updated May 7, 2018, 6:48 AM by Barbara Fortunato ]
5: M 5/7, 7: F 5/4

Today, we'll review what we learned about Lenz's Law last time and do a few examples.  Then we'll see if we can perpetually create a current in a loop of wire with only a little bit of work to start out.  

We'll watch a few cool videos:

Magnet brakes its own fall

Wireless Electricity

Levitating Barbecue! Electromagnetic Induction

Then, we'll introduce the quantitative formula for flux in a uniform magnetic field; ΦB = BAcosθ.  We'll see how we can quantify the current created by a changing magnetic flux in a loop by looking at Faraday's Lawε = -N ΔΦ/Δt where I = ε/R (Ohm's Law).

Presentation:  Electromagnetic Induction Presentation continued
Homework:  Try this for practice:  Magnetism Practice Quiz and check Answers.  Also, write a few sentences to explain how this works:

Lenz's Law Levitation