Topic 5: Energy and Earth Processes

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Topic 5 Energy and Earth Processes
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Energy Transfer Learning Objectives

• Describe the difference between kinetic and
  potential energy and give one real-life example
  of each.
• Describe the three ways energy is transferred
  between objects.
• Give at least one real-life example for each type
  of energy transfer.
• Explain how electromagnetic energy travels.
• Explain how types of energy are different apart.
• Give examples of materials which make the best
  absorbers and reflectors of energy.

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Temperature Learning Objectives

• Convert temperatures between the three
  temperature scales.
• Describe the relationship between temperature and
  molecular motion.
• Describe absolute zero in terms of molecular
  motion.

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Temperature Learning Objectives

• Explain the concept of specific heat in your own
  words and with real-life examples.
• Use the ESRTs to predict which earth materials
  will heat the fastest or slowest based upon their
  specific
• heats.
• Identify that water (liquid) has the highest
  specific heat of any Earth material.
• Explain why, in terms of specific heat, materials
  that are good absorbers are also good radiators.

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Heating of Water Learning Objectives

• Correctly label the water heating graph with the
  following characteristics freezing, melting,
  condensing, and evaporating.
• Identify when heat is being gained or lost by
  water on the water heating graph.
• Explain which phase changes require the biggest
  gains/losses of energy for water.
• Calculate the rate of temperature change for
  water.

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Energy
The ability to do work
Earths two Heat Engines
1) External
The sun drives surface processes
Effects
Wind patterns and ocean currents
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2.) Internal
Decay of radioactive elements
Effects
Plate tectonics
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Electromagnetic Energy
Form
Energy that travel in the form of waves
Characteristics
Wavelength
Distance from crest to crest
What is the name given to different types of
radiation?
Electromagnetic radiation
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Interactions Between Electromagnetic Energy and
the Environment
1) Refraction
Waves are bent due to density differences
2) Reflection
Light waves bounce off of materials
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3) Scattering
Waves are reflected and refracted in all
directions
Explanation
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4) Transmitted
Light waves are able to pass through
5) Absorbed
Light waves are taken into the material and
turned to heat
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Surface Properties of Absorption
Color
Dark absorbs and light colors reflect
Texture
Rough absorbs and Smooth reflects
Relationship between absorption and radiation
Good absorbers of radiation are also good
radiators!!!!!!
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Transfer of Energy
Direction of energy transfer
Always goes from high to low
Achieving Dynamic Equilibrium
Heat is transferred until temps. are equal
Types of Energy Transfer
1) Conduction
Energy moves from direct contact of particles
Materials
Most often with solids
Eureka
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2) Convection
Transfer of energy due to density differences
Materials
Only occurs in fluids (liquids and gasses)
Where does it occur?
Atmosphere and bodies of H2O
Eureka
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3) Radiation
The transfer of energy in the form of waves
Material
No medium necessary
The more energy an object has the more it gives
off!!!
Eureka
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Transformation of Mechanical Energy
Mechanical Energy
The total kinetic and potential energy in a system
Kinetic Energy
The energy of motion
Mass and velocity
Factors of K.E.
Potential Energy
Stored energy
Factors of P.E.
Mass and position
Transformation of P.E. to K.E.
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Transformation of Electromagnetic Radiation
What is the relationship between temp. and
wavelength of light that is radiated?
Smaller Wavelength More Energy
Does the sun radiate shorter or longer
wavelengths of light than earth ?
Shorter (Sun emits UV and Visible)
Which wavelength of light is radiated from earth?
Infrared
Can This Be A Problem ????
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Greenhouse
Doom and Gloom
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Temperature and Heat
Kinetic theory of matter
All matter is made of atoms that are moving
Temperature
Average kinetic energy of a system or object
What is the relationship between kinetic energy
and temp.?
Direct
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Heat and Thermal Energy
Hot
Energy leaves the object and goes to body
Cold
Energy leaves the body and goes to object
Calorie
Energy needed to change the temperature of one
gram of water 10 c
Liquid water has a higher specific heat than any
other natural substance!!!!!!!!!
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Heat Energy and Changes in State
Melting
Solid to liquid
Freezing
Liquid to a solid
Solidification
Liquid to a solid
Evaporation
Liquid to a gas
Condensation
Gas to a liquid
Sublimation
Solid directly to a gas
Precipitation
Gas directly to a solid
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Notice what Happens to Temperature
Temp. increases (molecules move faster)
From -100 to 0
During melting
Bonds break (334 J/g used)
0-100
Temp. of liquid water increases
Water being liberated (2260J/g used)
During Vaporization
100 to 200
Temp. of gaseous water increasing
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Earths Energy Supply
Solar Energy
Visible and Ultraviolet
Wave lengths
Most Intense
Shortest wavelength (UVsunburn)
Nuclear Fusion
What Produces Solar Energy
Secrets of the Sun
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Earths Own Energy
1) Remains from when earth first formed
2) Materials that are under extreme pressure
3) Radioactive decay of elements
Overwhelming