ELECTROMAGNETISM: HOW TO BUILD YOUR OWN ELECTRIC CAR By Fernando Olmos 5/23/13

Lesson Outline  Day 1  Brief Presentation on electromagnetism and electric cars  Do It Yourself (DIY) activity 1 – How to build a battery  Day 2  DIY activity 2 – How to build an electric motor  Wrap-up

Goals  Understand how electromagnetism principles apply to electric cars  Learn how an electric motor works  Learn how a battery works  Learn the basic concepts on how to build an electric car  Learn features of electric cars

Review of Electromagnetism I  An electric current produces magnetism, and a magnet can produce an electric current

Review of Electromagnetism II  Electricity creating magnetism  Each electron has an electric field  When the electron moves, it also creates a magnetic field  When electrons move through a conductor (metal or coil of wire) the conductor becomes an electromagnet.

Review of Electromagnetism III  Magnetism creating Electricity  Coil of wire placed near a magnet  Change the magnetic field by moving the magnet back and forth or spinning the wire  Changing magnetic field produces and electric current in the wire

How do Electric Motors Work? I  A current turns a conductor into an electromagnet  When the electromagnet is placed near a fixed magnet, the two sets of poles repel and attract each other  This produces a force that makes the conductor rotate (spin) at high speed, which turns a shaft

How do Electric Motors Work? II

How do batteries work?  First battery: voltaic pile by Alessandro Volta in 1800  Electrons move from one metal to the other metal through a saltwater solution  Saltwater solution is called an electrolyte  Contains ions in solution from the dissolved salts  Ions react with the metals making electrons.  Metal are called electrodes  Electrical potential difference (voltage); one positive, one negative  Electrons move, creating an electrical current

Electric Car Features  Runs on an electric motor  100% pollutant emission free  Gets power from batteries, wind, or sun  Motor is way smaller than gasoline engine  Quiet to drive  Limited range (~60 to 100 miles)  More frequent refueling  Charging time takes hours

Electric Car Features