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Currently Playing: Lenz’s Law – Understanding electromagnetic Induction PART 2 – High School Physics

Electromagnetic Induction is the process by which mechanical energy can be converted to electrical energy and vice et versa. In other words, it is at the heart of modern technology. This is why it is so fundamental for any student in physics to possess a solid understanding of electromagnetic Induction. In the first video of this series, we discussed Faraday’s law that states that an induced emf is proportional to the rate of change of magnetic flux. For a single looped circuit, the proportionality constant is actually -1 (minus 1). The minus sign is an expression of Lenz’s Law. In this video, we explain why. Lenz’s law is the subject of this video. We discuss how the fact that Lenz’s law imposes the direction of the induced emf generates a negative feedback loop that tends to oppose what is inducing this emf in the first place! Yes, Lenz’s law states that an induced emf is in a direction such that it opposes what induces it. In a second section, we discuss why this happens: Lenz’s law can be seen like an electrical version of friction, so keeping the motion going imposes that work be done on the system. We derive how much energy is dissipated by the circuit and compare it to the energy input based on the work needed to keep that motion constant. This shows us how Lenz’s law is just a reflection of the principle of conservation of energy. - - - - - - - - - STRUCTURE OF THE VIDEO 00:00 How Lenz’s law is contained in faraday’s Law (introduction) 00:36 Prior knowledge required for this video about Lenz’s Law 00:57 Lenz’s Law: a negative feedback loop 03:57 Induction of a voltage in a conductor moving in a magnetic field. 03:01 Lenz’s law and conservation of energy 06:30 What is Lenz Law (conclusion). 06:53 Faraday’s Law and Lenz’s law: the two pillars of electromagnetic induction - - - - - - - - - VIDEOS TO WATCH: Faraday’s law – understanding electromagnetic Induction Part 1 https://www.youtube.com/watch?v=HmBvWgK7fsQ&list=PLU0ETLdKNmc6nrvb9vLIefhTjktqnZM3G&index=4 What is an electric Field? https://www.youtube.com/watch?v=hrHCj09_dpc&list=PLU0ETLdKNmc6nrvb9vLIefhTjktqnZM3G&index=8 What is an electric potential? https://www.youtube.com/watch?v=j3GrOKre__0&list=PLU0ETLdKNmc6nrvb9vLIefhTjktqnZM3G&index=6 What is a magnetic Field? https://www.youtube.com/watch?v=NOQK57fgu80&list=PLU0ETLdKNmc6nrvb9vLIefhTjktqnZM3G&index=2 What is Flux ? https://www.youtube.com/watch?v=ANXIdrb30dc&list=PLU0ETLdKNmc6nrvb9vLIefhTjktqnZM3G&index=3 The link between electric potential and electric field strength : https://www.youtube.com/watch?v=RMr3bk8DD1k&list=PLU0ETLdKNmc6nrvb9vLIefhTjktqnZM3G&index=1 The conventional current https://www.youtube.com/watch?v=XzPOGFgsJfE&list=PLU0ETLdKNmc5CUU9L5J6JTYHTPRZFA9I1&index=1 - - - - - - - - - MUSIC ALBUM Physics Made Easy « The soundtracks ». Listen to the it here: https://edouardreny.bandcamp.com/album/physics-made-easy-the-soundtracks - - - - - - - - - CREDITS: The script, the illustrations, the music and the video were produced and presented by Edouard Reny, Ph.D. in solid state chemistry and private tutor in Physical Sciences. - - - - - - - - - DO YOU NEED HELP WITH YOUR HIGH SCHOOL PHYSICS? Edouard provides one-on-one private tuition in Physics (face to face or by Skype). If you wish to know more about this, or contact Edouard, visit his website: https://www.physics-tutor.nl/ or this one (for French speakers: https://www.profdephysique.fr/). - - - - - - - - -