ENERGY

What is Energy?• The ability to do work or cause

change• It occurs in different forms:

–Electrical, chemical, light, mechanical

• Energy comes in TWO different states…

Potential Energy

• Stored Energy– This energy may be found:

• In the position of an object above a specific point

Potential Energy

• Stored Energy– This energy may be found:

• In the chemical composition of the object or substance

Potential Energy

The food we eat is also potential energy…

Why??

Realizing its potential…

• What happens to that stored potential energy?

Kinetic Energy

• The other form of energy

• The energy of motion• Most often seen at the

molecular or atmoic motions of the particles of matter

Kinetic Energy

• The larger the mass, the greater the kinetic energy.

• Velocity also affects the kinetic energy- it causes a greater change than a change in mass.

• (Velocity, by the way, is the speed and direction an object is moving in)

Forms of Energy

• Heat energy– Produced by the movement of atoms, ions

and molecules– Difference between Heat and Energy?

Mechanical Energy

• Energy used and by moving machinery or objects doing work

Electrical Energy

• Movement of electrons

Chemical Energy

• Energy stored in the chemical bonds of food, fuel or natural gas.

• Produces other forms of energy

Light Energy

• Travels through waves• A visible form of electromagnetic waves

Laws of Energy

Law of Conservation of Energy The First Law of Energy

Energy can neither be created nor destroyed.

Laws of Energy

• This means that the total amount of energy leaving a system is equal to the total amount of energy that entered the system.

• Law of Conservation of Mass (also known as the Law of conservation of Matter)– Matter can neither be created nor destroyed

Laws of Energy

• Second law of energy– Deals with thermal process.– Heat can only flow from hot to cold, so the energy

flow is one way.– Energy is not 100% efficient. There will ALWAYS

be a loss of energy (car engine example)– Energy that is lost and converted into unusable

forms is called Entropy.

Key terms

• Energy• Potential Energy• Kinetic Energy• Heat energy• Mechanical energy• Electrical energy• Chemical energy• Light energy• Law of Conservation of Energy