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?