Transfer of Energy

Energy Conservation and Conservation

Learning Targets

KNOWLEDGE Know that there are different forms of energy Understand that energy can change forms, but it is never

lost SKILL

Using photograph or illustration, identify how potential and kinetic energy are being transferred

Reasoning Analyze how energy goes through transformations

Product Draw and label a diagram that shows different energy

conversions

Questions to Think About

How are different forms of energy related? Examples. Think about when you rub your hands together. When you are cold how do you warm up.

What is the Law of Conservation of Energy?

Major Forms of EnergyMechanical Energy

Thermal Energy

Chemical Energy

Electrical Energy

Electromagnetic Energy

Nuclear Energy

Conversions Between Forms of Energy

Energy Conversion A change from one form

of energy to another

Also know as a energy transformation

Any form of energy can be converted into any other form

Energy Conversions

Energy ConversionsElectromagnetic

Move Muscles

Heat Body

Brain Thinking

Electromagnetic

Energy Conversions

Electromagnetic

Energy ConversionsHot Spark

Burning Gas

Car Moving

Electromagnetic Engine

Energy Conversions

Kinetic And Potential ConversionsMost common energy conversions is the conversion of potential energy to kinetic energy.

Energy Conversion in Juggling Any object that rises or falls

change in its KE and PE

Movement=KE

Rises=decrease in KE and increase in PE

Highest Point=movement stops and high in PE and no KE

Falls=decrease in PE and increase in KE

Energy Conversion in Waterfalls With waterfalls PE gets

converted to KE on a large scale

Water at the top has a lot of PE due to height

As the water falls, its height decreases and it loses PE

At the same time, its KE increases because the velocity increases

Energy Conversion in Pole Vault Pole vaulter runs=PE

Plants pole to jump and pole bends= Elastic PE

Pole straightens out and pole vaulter is lifted high in the air= Gravitational PE

Gravitational PE is converted to KE as the pole vaulter falls to the ground

Energy Conversion in a Pendulum

Continuous conversion of KE and PE

At the highest point of the swing the pendulum only has Gravitational PE

As the pendulum starts to swing downward, it speed up and converts to KE

At the bottom of the swing all of its energy is KE

As it swings to the other side the pendulum slows down, regains Gravitational PE and loses KE

At the the top of the other side it again has only Gravitational PE

Conservation of Energy Is energy destroyed over

time?

LAW OF CONSERVATION OF ENERGY States that when one form of

energy is converted to another, no energy is destroyed in the process

Energy cannot be created or destroyed

All energy is accounted for-total amount of energy is the same before and after any process

Energy and Friction What cause the pendulum to stop swinging?

Friction at pivot point of the string

Friction of the pendulum through the air

Atoms and molecules increase movement with when something experiences friction

Thermal energy increases

Mechanical energy is converted to thermal energy

Pendulum slows down, but is energy is not destroyed

Rub cold hands together to warm them up (mechanical to thermal transfer)

Conserving Energy

Conserving EnergyMeans SAVING energy, or not WASTING it

Not wasting fuels such as gasoline or other resources

Energy is always conserved because its total quantity does not change