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11.1. Electromagnetic Induction (HL)

Here we look back at the topics of electricity and magnetism. Michael Faraday was a hugely influential figure who did a lot of important work around understanding electricity and its relationship with magnetism (essentially leading to the subsequent important work by James Clerk Maxwell). He lends his name to Faraday's Law - a law which describes how an EMF is induced from moving a conductor in a magnetic field. For a bit of historical context to the chapter, take a look at this video by SciShow.

The section has been divided up as follows:

Inducing an EMF - introducing how we can generate an EMF in a conductor

Flux and Flux Linkage  - a few key bits of terminology we need to get to grips with

Faraday's Law - a very important equation described by Michael Faraday

Lenz's Law - where does the force opposing motion come from?

 

Inducing an EMF in a Conductor

We have previously looked a little bit at the motor effect - that is moving charges experiencing a force in a magnetic field. Here we look at what is sometimes called the 'dynamo effect'. 

Video Lessons

Chris Doner
EM Induction
IB Specific
Khan Academy
Induced Current in a wire
Induced EMF in a rod
Science Shorts
EM Induction

Resources

IB Physics
Topic 11 Notes
IB-Physics.net
Chapter 11 Summary
IB Revision Notes
Mr. G
11.1 Teaching Notes
11.1 Student Notes
Physics and Maths Tutor
Fields Definitions
Fields Key Points
Fields Detailed Notes
B Field Flashcards
A Level Resources - content slightly different

Questions

 

Magnetic Flux and Flux Linkage

There are a few key terms we need to get to grips with to understand this topic. When we discussed magnetic fields back in Section 5.4, we introduced the term 'Magnetic Flux Density' to mean the same thing as 'Magnetic Field Strength'. When thinking about those magnetic field diagrams the flux density can be thought of as how close those field lines are together, i.e the density of the lines of flux per unit area.

Video Lessons

Chris Doner
EM Induction (Flux)
IB Specific
Khan Academy
Flux
Science Shorts
Flux Intro

Resources

IB Physics
Topic 11 Notes
IB-Physics.net
Chapter 11 Summary
IB Revision Notes
Isaac Physics
Magnetic Flux
Gauss Law
Extension : Gauss Law beyond IB
Mr. G
11.1 Teaching Notes
11.1 Student Notes
Physics and Maths Tutor
Fields Definitions
Fields Key Points
Fields Detailed Notes
B Field Flashcards
A Level Resources - content slightly different

Questions

Cambridge University Press
Topic 11: MCQs
CUP Website Link
Freely available online
Dr French's Eclecticon
Electromagnetism
Electromagnetism Solutions
Link to Dr French's Site
Extension: Pre-University Material
Grade Gorilla
11.1 (Induction) MCQs
Topic 11 (Induction) Final Quiz
Quick IB Specific Mixed MCQs
Isaac Physics
Magnetic Flux and Faraday's Law
Mixed Questions
Mr. G
11.1 Formative Assessment
Topic 11 Summary Qs
IB Specific Questions
Physics and Maths Tutor
Flux Density (AQA 2)
Flux Density MS (AQA 2)
Flux & Flux Linkage (AQA 2)
Flux & Flux Linkage MS (AQA 2)
A-Level Qs: overlapping content
 

Faraday's Law of Electromagnetic Induction

Video Lessons

Chris Doner
EM Induction (Faraday's Law)
IB Specific
Gradepod
Faraday's Law
AC Generators
IB Specific
Khan Academy
Faraday's Law Intro
Science Shorts
Induced EMF and Faraday

Resources

IB Physics
Topic 11 Notes
IB-Physics.net
Chapter 11 Summary
IB Revision Notes
Isaac Physics
Faraday's Law
Mr. G
11.1 Teaching Notes
11.1 Student Notes
Physics and Maths Tutor
Fields Definitions
Fields Key Points
Fields Detailed Notes
B Field Flashcards
A Level Resources - content slightly different

Questions

 

Lenz's Law

Lenz's Law tells us all about the direction of the induced EMF described by Faraday. It essentially all comes back to the conservation of energy. Before we look in more detail, I'll leave it to VSauce to introduce things (his MRI demo is my favourite).

Video Lessons

Resources

IB Physics
Topic 11 Notes
IB-Physics.net
Chapter 11 Summary
IB Revision Notes
Isaac Physics
Lenz's Law Introduction
Mr. G
11.1 Teaching Notes
11.1 Student Notes
Physics and Maths Tutor
Fields Definitions
Fields Key Points
Fields Detailed Notes
B Field Flashcards
A Level Resources - content slightly different

Questions

 

Additional Resources

IB Questions

A question by question breakdown of the IB papers by year is shown below to allow you to filter questions by topic. Hopefully you have access to many of these papers through your school system. If available, there may be some links to online sources of questions, though please be patient if the links are broken! (DrR: If you do find some broken links, please contact me through the site)

Questions on this topic (Section 11) are shown in green.

Use this grid to practice past IB questions topic by topic. You can see from the colours how similar the question topic breakdown is year by year. The more you can familiarise yourself with the IB question style the better - eventually you will come to spot those tricks and types of questions that reappear each year.