Energy and Transformation of Energy

Energy Definition• The ability to do work.• How do we use energy?• Energy comes from heat,

chemicals, electricity, fossil fuel, and the food you eat.

I. Types of EnergyA. Chemical

• Definition: is energy contained inside substances.

• Released during chemical reactions• Examples of chemical energy are:

gasoline, coal, and oil• By breaking chemical bonds energy is

released for use.

Types of EnergyB. Solar Energy

• Definition: Energy that comes from the Sun.

• Examples: visible light, ultraviolet light, and heat energy.

Types of EnergyC. Electrical Energy

- Definition: energy from the movement of electrically charged particles.

- Power plants produced electrical energy from other energy sources such as coal (chemical), oil (chemical), wind (mechanical), and nuclear power (nuclear).

Types of EnergyD. Mechanical Energy- Definition: is the energy an

object has because of motion.

- Kinetic Energy : energy of motion- Potential Energy: energy of

rest/position

Types of Energy• E. Thermal Energy

• Definition: Energy resulting from the motion of particles. Thermal energy is a form of kinetic energy and is transferred as heat.

Transformation of Energy• LAW OF CONSERVATION OF

ENERGY• Definition: This states that energy

can change from one form to another, but it cannot be created or destroyed.

• Important: When energy is used, it does not disappear……it simply changes to another form.

Heat Energy Transfer• This type of energy can be transferred from

one object to another when there is a temperature difference between them.

• Movement of this energy moves from hot to cold.

• The reason a hot chocolate mug feels warm to your hand is because the heat is moving from the hot mug to your colder hand. Some of the heat also moves to the air (hot to cold).

Energy Transformation• Explain how energy transformation

occurs when you turn on a flashlight?

• Chemical Energy (batteries). When you turn on the switch Chemical Energy transforms into Electrical Energy. Electrical Energy is then transformed to Light Energy. Light Energy is transformed into Heat Energy (thermal)

Waves• Definition: is a disturbance that

transfers energy from one place to another.

• Examples: (Mechanical Waves) earthquake waves, sound waves, water waves. Electromagnetic waves (x-rays, light, and radio waves)

Mechanical Waves• Some kinds of waves travel through

matter.• The energy is transferred by waves is

carried from its source by vibrations.• The waves travel through material or a

medium.• Medium can be a gas, liquid or solid. • Waves that require a medium are called

mechanical waves.

Electromagnetic Waves• Not all waves need a medium to

transfer energy.• Visible light, infrared light, microwaves,

radio waves, ultraviolet light, x-rays, and gamma rays can travel through empty space.

• These are called Electromagnetic waves.

• Def: is a disturbance caused by an electric field and a magnetic field changing and moving together.