AP_Physics_B_-_Electromagnetic_Induction

# AP_Physics_B_-_Electromagnetic_Induction - AP Physics B...

This preview shows pages 1–8. Sign up to view the full content.

ElectroMagnetic Induction AP Physics B

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
What is E/M Induction? Electromagnetic Induction is the process of using magnetic fields to produce voltage, and in a complete circuit, a current. Michael Faraday first discovered it, using some of the works of Hans Christian Oersted. His work started at first using different combinations of wires and magnetic strengths and currents, but it wasn't until he tried moving the wires that he got any success. It turns out that electromagnetic induction is created by just that - the moving of a conductive substance through a magnetic field.
Magnetic Induction As the magnet moves back and forth a current is said to be INDUCED in the wire.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Magnetic Flux The first step to understanding the complex nature of electromagnetic induction is to understand the idea of magnetic flux. Flux is a general term associated with a FIELD that is bound by a certain AREA. So MAGNETIC FLUX is any AREA that has a MAGNETIC FIELD passing through it. A B We generally define an AREA vector as one that is perpendicular to the surface of the material. Therefore, you can see in the figure that the AREA vector and the Magnetic Field vector are PARALLEL . This then produces a DOT PRODUCT between the 2 variables that then define flux.
Magnetic Flux – The DOT product Wb) or Weber( Tm : Unit cos 2 θ BA A B B B = Φ = Φ How could we CHANGE the flux over a period of time? We could move the magnet away or towards (or the wire) We could increase or decrease the area We could ROTATE the wire along an axis that is PERPENDICULAR to the field thus changing the angle between the area and magnetic field vectors.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Faraday’s Law Faraday learned that if you change any part of the flux over time you could induce a current in a conductor and thus create a source of EMF (voltage, potential difference). Since we are dealing with time here were a talking about the RATE of CHANGE of FLUX, which is called Faraday’s Law. wire of turns # ) cos ( = - = ∆Φ - = N t BA N t N B θ ε
Useful Applications The Forever Flashlight uses the Faraday Principle of Electromagnetic Energy to eliminate the need for batteries. The Faraday Principle states that if an electric conductor, like copper wire, is moved through a magnetic field, electric current will be generated and flow into the conductor.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 20

AP_Physics_B_-_Electromagnetic_Induction - AP Physics B...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online