Presentation on theme: "Current Electricity. What is Current Electricity? Think of all the ways you use electricity each day. You awake to an alarm clock or the radio, turn on."— Presentation transcript:
What is Current Electricity? Think of all the ways you use electricity each day. You awake to an alarm clock or the radio, turn on an electric light, use an electric toothbrush or make toast. You watch television, listen to music, and use air conditioners. Just think about lights. Almost every place you go you find electrical lighting. **Don’t copy just think about it!
About one hundred years ago there was no electricity in homes, schools, factories or offices. Try to imagine your life without electricity! In your notebook write down 5 things that would be very difficult to do if you didn’t have electricity.
The electricity that works all of your electrical appliances is called Current Electricity. A current is a flow or stream. Current electricity comes from a flow of electrons. Electrons are the parts of the atom that give it the negative charge.
Electrons move along a path called a circuit. While the electrons are moving, the circuit is complete. If the electrons stop moving, the circuit is incomplete and the electricity stops.
Some of our electricity comes from batteries. Small batteries like those used for flashlights are called dry cells. Most of our electricity comes from machines called generators. Each year the world uses more and more electricity. More and more generators are needed.
How do we generate electricity? In your notebooks list 5 ways
Some power stations use water to spin giant generators. These are called Hydro Power Plants. Hydro means water. Hydro
Wind Power The power of the wind turns the blades and rotor of the wind turbine The rotor is attached to a shaft which spins and this energy is captured and converted into electricity by a generator
Nuclear Power Provides 13% of the world’s electricity Captures the energy from a nuclear reaction (on a large scale) to create electricity and heat Very efficient heat/energy source Clean burning energy but the waste that it leaves behind is highly toxic
Solar Power Solar mirrored panels gather the sunlight The photovoltaic cells collect, condense and convert the sun’s energy into an electric current or uses the energy to boil large amounts of water which is then used to generate heat and electricty Can be harnessed commercially (for mass uses) or on a small scale (home owners)
Nova Scotia Electricity Here we mostly burn coal or oil to make steam which is then used to spin the coils of the generators. These types of power plants are known as thermal power plants (Thermal)
Electrical generators are turning mechanical energy into electrical energy These large generators are producing alternating current.
Making Current Electricity Current electricity can also be made by chemical means. A battery is a device which makes electricity by using chemicals. Electricity always flows from the negative to the positive. Batteries use this principal to make current electricity.
Researchers found that the simplest electricity making unit or electric cell was two plates of different metals in a jar filled with liquid. The metal plates are called electrodes. They are conductors. The positive electrode is called the anode The negative electrode is called the cathode.
Kinds of Batteries There are two kinds of batteries: –One which has liquids in it –One which is made from dry substances A battery in your car has liquid acid in it. A battery in your flashlight is a dry cell battery. It is made with dry substances. Dry cell batteries are safer and more convenient to use.
A battery is basically made up of two different chemical substances. One substance has a negative charge and the other substance has a positive charge. When a pathway is made between these two substances electricity will flow from the negative pole to the positive pole