generating electricity. what is energy? energy has many different forms. when an object is able to...
TRANSCRIPT
What Is Energy?
• Energy has many different forms. • When an object is able to change its
environment, we say the object has energy.• Energy is the ability to do a task, such as
moving an object.
Common Forms of EnergyForm of energy Examples
Chemical - Gasoline; food; fireworks
Thermal - Warmth from a fire
Sound - voices; music
Radiant (light) - sunlight; microwaves
Mechanical - wind; running water
Electrical - lighting; electricity for your home
Energy Transformations
• There are many ways to change or transform one form of energy into another form.– Your body and a car’s engine change chemical
energy into mechanical energy.– When you bang a drum, the mechanical energy is
changed into sound energy.– A wind turbine changes mechanical energy into
electrical energy.
Examples of Energy Transformations
Example Energy Transformations
Solar panel Light energy electrical energy
Fire Chemical energy thermal energy and light energy
Wind turbine Mechanical energy electrical energy
Car engine Chemical energy thermal energy mechanical energy
Light bulb Electrical energy thermal energy and light energy
Generating Electrical Energy
The Grid:• Most or the electrical energy we use comes to
us through the electrical energy distribution grid.
• The electrical energy distribution grid is a network that carries electricity from the energy generating station to the consumer.
Generators:• Most energy is distributed by the gird is
produced in electrical energy generating stations.
• These stations use generators.• A generator is a machine that converts
mechanical energy into electrical energy.
• The energy in the wind, flowing water, or stream can be converted into electrical energy.
• The movement is used to push blades of a fan-like device called a turbine.
• The turbine is connected to the wire coils inside a generator.
• When the turbine spins, the coils of a wire generate electrical energy as they spin at high speed near powerful magnets.
Measuring Electrical Energy
• All energy is measured in joules (J).• How quickly we use electrical energy can be
measured as the number of joules used per second.
• A joule per second is called a watt (W).• A 20 W bulb uses 20 J or energy per second.