Section 2.1- Charged Up! Science

 Before we begin discussing electricity, we need to discover what we already know about the subject. Here is your assignment: ◦ Electricity KWL Plus Chart: complete the “K” and “W” sections of the KWL chart. What do you already know about electricity? What do you want to learn about electricity?

 Explain how electric current is generated.  Define mechanical energy and electrical energy.  Describe the energy conversions that take place in different kinds of power plants. ◦ How is mechanical energy converted to electrical energy.

 A form of energy  Results in the flow of electrons in a wire or other conductor.  What are electrons?

 OF COURSE NOT!  For hundreds of years people lit candles and built fires to get light. They made clothes and furniture.  Discovery of electricity led to the supply of electricity to light cities, run factories, and make it possible to watch television!  How would your life be without television?

 In 1820, Danish scientist Hans Oersted discovered that if electric current flows through a wire, it could move a nearby compass needle.  Ten years later, an English scientist, Michael Faraday, and an American scientist, Joseph Henry, each showed that a magnet could be used to produce electric current.

 Discovery that magnetism can produce an electric current led to the invention of the generator.  Generator: is a machine that uses a magnet to change mechanical energy, or motion, into electrical energy, or current.  Consider the Faraday and Henry experiment.

 A magnetic field surrounds a magnet. If you slide a paperclip toward a magnet, what happens?

 Voltage is the force that causes electrons to move though the wire. Voltage is measured in volts.  The current that flows through the wire is measured in amps.  Power is the amount of energy given up every second by a current. Power is measured in watts.

 Hydroelectricity is electricity produced from flowing water through a turbine.  A turbine is a machine that can be turned by flowing gas or liquid.

 Power plants also use fuels to generate electricity. Some plants use nuclear fuels, but many use fossil fuels such as coal, oil, or natural gas.

 What are three ways electricity can be produced?  What is the difference between mechanical and electrical energy?