electromagnetism: how to build your own electric car by fernando olmos 5/23/13
TRANSCRIPT
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 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