Energy: Conservation and Transfer. Energy can be transferred from one system to another or to the...

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Energy: Conservation and Transfer

Energy can be transferred from one system to another or to the environment in different ways.

It is transferred through a material by the collisions of the atoms in that material.

Mechanical energy-when two objects push or pull on each other over a distance

-Sum of the energy in a mechanical system-combination of potential and kinetic

energy

Electrical energy when an electrical source such as a battery or generator is connected in a complete circuit to an electrical device

Electromagnetic Waves -radiation travels as electromagnetic waves -light, microwaves, x-rays, and TV and radio transmissions

Energy: Conservation and Transfer

6.P.3.2

Light and Energy Interaction

Light and other electromagnetic waves can warm objects› How much it’s temperature

increases depends on: Intensity of the light Duration- How long it shines on it Absorption- How much light is absorbed

Light and Energy Interaction

When light interacts with matter it is either:› Absorbed› Reflected› Transmitted

Energy Sources

The sun is a major source of energy for changes on the earth’s surface› It loses energy by emitting light› Only a tiny fraction of light reaches the

earth (transferring energy from the sun to the earth)

Sun’s Energy

Arrives as light with a range of wavelengths consisting of:› Visible Spectrum› Infrared light› Ultraviolet Light

Visible Spectrum

The portion of electromagnetic spectrum that is visible to human eyes

Called Visible light or simply light

Mr. Parr Electromagnetic Spectrum- Click Here

Infrared light

Has longer wavelengths than visible light

Most often detected by is heating effect

Used in Space Exploration and Satellite Imaging

Ultraviolet Light shorter wavelengths that visible light Same type of waves used in tanning

bed lights Cause Sunburn Most of these are blocked from

reaching us by the ozone but some days more are able to get past

UV Index› Created to help people protect themselves

from these harmful waves

Energy Part 3

Thermal Energy Total potential and kinetic energy of the particles in an object

Conduction Heat is transferred from one

particle to another without the movement of matter

Particles must be in contact

Mr. Parr Heat Transfer

Expansion The expanding of a material

when heated As the thermal energy of

matter increases, its particles spread out and the substance expands.

Contraction As the thermal energy of matter

is lost, the particles of the matter move closer together.

Electrical Energy The energy of electric charges Can be kinetic (used) or

potential (stored) Examples: lightening,

batteries, power lines

Conductor Transfers thermal energy well Conducts heat Examples of good conductors:

metals and tile floors

Copper Wire

Insulator Does not transfer thermal energy

well Does not conduct heat Examples of good insulators:

wood, wool, straw, paper, gases in the air, clothes, blankets

Which part is the conductor and which part is the insulator?

Thermal Energy and Electrical energy in Technology

Geothermal Heating Systems, Solar Panels, Electricity, and a whole lot more

These technologies use thermal (heat) energy and electrical energy to power things

Conservation of Energy

Mr. Parr Conservation of Energy

Mr. Parr The Heating song

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