HP Cycle 39

Then, we'll take a look at a moving bar in a magnetic field which will produce a motional emf.  Using what we learned last time about Faraday's Law, we'll derive an equation that can help you understand this relationship.  (Faraday's Law, ε = -N ΔΦ/Δt and I = ε/R (Ohm's Law)).  Watch the video.  

Then, we'll practice motional emf problems by doing problem solving.

Homework:  QUIZ on basic magnetism (magnetic field lines, force on a moving charge and current carrying wire, field created by current, mass spectrometer, right hand rules, force equations) on Tuesday, May 19th.

Optional Extra Practice:  📖 Mastering Physics "Ch 25 - motional emf" problems #C3, C18, 4, 7, 62, 65.  Read any sections in chapter 25.1-3 that seem unclear.  Then do at least #11-12 of page 2 of FYP: Electromagnetism  (ANSWERS). The video will help you with these two problems.  

Today, we'll see how transformers work and how they can be useful.   We'll use Faraday's Law of Induction to derive the relationships between primary/secondary numbers of coils, voltage, and current in ideal transformers.  (Know the ideal transformer equation.)