 # Energy and Energy Resources

## Presentation on theme: "Energy and Energy Resources"— Presentation transcript:

Energy and Energy Resources
What Is Energy (chapter 5 section 1) Energy Conversions ( Chapter 5 sec 2)

What is Energy? Energy is the ability to do work
Work occurs when a force is applied to an object in the same direction that the object moves Energy is transferred from one object to another

Kinetic Energy Kinetic energy(KE) is the energy of motion
All moving objects have kinetic energy The amount of kinetic energy that an object has can be calculated by the following formula: KE= mv2/2 (m = mass v = velocity or speed) The more mass an object has, the more kinetic energy it has The faster an object is moving, the more kinetic energy

Potential Energy Potential energy is the energy that an object has because of its position; it is STORED ENERGY (has the potential to do work) Gravitational Potential Energy (GPE) Elastic Potential Energy

Gravitational Potential Energy
Gravitational Potential Energy is energy that is stored due to the gravitational attraction of the Earth on the object When an object is lifted up off of the ground, a force is applied to lift the object. The energy used to lift the object is stored in the object GPE is calculated with the formula GPE = Weight X height Units = Joules ( newton/meters)

Elastic Potential Energy
Energy stored as a result of the deformation (changing the shape) of an elastic object Examples: Stretching a spring Stretching an elastic band

Mechanical Energy Mechanical Energy (ME) is the total energy of kinetic(KE)and potential energy (PE) ME = KE + PE As KE increases, PE decreases As KE decreases, PE increases

Kinetic and Potential Energy Video
The Story of Kinetic and Potential Energy

Other Forms of Energy (most can exist as potential and kinetic forms)
Thermal energy – the energy that exists due to the kinetic energy of moving atoms that make up the matter

Other Forms of Energy (most can exist as potential and kinetic forms)
Chemical energy – the energy that comes from the rearrangement arrangement of atoms Food energy is a type of chemical energy Electrical energy – the energy of moving electrons

Other Forms of Energy (most can exist as potential and kinetic forms)
Sound energy – the energy caused by an objects vibration; travels in waves Must have a medium (matter) to travel Light (radiant) energy – the energy produced by the vibration of electrically charged particles; exists as a wave and a particle Does not need a medium to travel; can travel in a vacuum(where the is no matter)

Other Forms of Energy (most can exist as potential and kinetic forms)
Nuclear energy – the energy that comes from changes in the nucleus of an atom Fusion – the joining of nuclei Fission – the splitting of nuclei

The Seven Forms of Energy Video Clip

All forms of energy can change (convert) into other forms of energy
Energy conversion is a change from one form of energy to another

Examples of energy conversions
Potential to kinetic Kinetic to potential

Examples of energy conversions
Food energy(chemical) to mechanical or kinetic energy ( cereal for breakfast used to allow you to move)

Conversions Involving Chemical Energy In Plants

Why Energy Conversions Are Important
Energy conversions are needed for everything we do Without energy conversions we could not live or do all the things we do Machines can make work easier by converting energy into the form of energy needed to do the work. Not all energy conversions are useful for the work that you are trying to do – some is “wasted” energy

Energy and Machines