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Dive into the fascinating world of electromagnetism with a focus on Faraday's and Lentz's laws. Discover the implications of changing magnetic fields and induced currents, highlighting how Lentz's Law illustrates the opposition of induced magnetic fields to their source. This activity includes practical demonstrations, such as the infamous Pipe Demo, and explores concepts like induced emf and the relationships detailed in Maxwell's equations. Join us in a stimulating exploration of how these fundamental principles govern electromagnetic interactions in various scenarios!
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Faraday and Lentz Good friends??
Ring around the Ring
From Faraday This -dB/dt is important NC
Last Time - Maxwell Coulomb/Gauss Gauss – Magnetism Faraday’s Law Extended Ampere’s Law
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From Before .. as a reminder This -dB/dt is important
The power supply is slowly turned up, increasing the current in the solenoid. The initial B is show on the diagram. The current increases so B increases as well by dB in time dt. Effect is a field reduction caused by the induced current which must be opposing the original current (- sign). The net emf is reduced as is the current. (Ohm’s Law). The induced current opposes I. B The total emf is changed (reduced ) by this amount.
The power supply is slowly turned up, increasing the current in the solenoid. B What does Lentz tell us??? The total emf is changed (reduced ) by this amount.
Remember the Pipe Demo S N Aluminum Pipe • Do you remember it? • Can you explain it? • Mini Activity on the Pipe • Whiteboard Presentation
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