1. Basics in Magnetism Electromagnetism Force on a Current-Carrying Wire EM Induction Transformer Generators Electric Motors ELECTROMAGNETISM

2. What happens when you move a magnet into a coil of wire? Michael Faraday EM Induction Changing magnetic field can produce electricity!

3. How is a changing magnetic field produced? Using AC source Moving magnet in a coil of wire Moving wire in a magnetic field

4. What factors affect the emf produced? The number of loops The speed of the magnet The size of the coil of wire More turns, greater emf Faster, greater emf Greater size, greater emf

5. What factors affect the emf produced? The polarity of magnet Direction of motion Strength of Magnet Changes direction Greater strength, greater emf

6. The AC Generator Top view Allows contact with the rings while allowing them to slip past Prevents the wires from twisting

7. The AC Generator

8. The Transformer

9. Causes changing magnetic field Makes the field stronger Emf is induced in the coils

10. The Transformer V s > V p Step down transformer V s < V p Charging electronic gadgets Step up transformer Power transmission

11. Power Transmission There is less current at high voltage. Power loss is lower at high voltage.