topic 5: energy and earth processes. energy transfer learning objectives describe the difference...
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Topic 5: Energy and Earth Processes
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.
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.
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.
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.
Energy: The ability to do work
Earth’s two Heat Engines
1) External: The sun drives surface processes
Effects: Wind patterns and ocean currents
2.) Internal: Decay of radioactive elements
Effects: Plate tectonics
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
Interactions Between Electromagnetic Energy and the Environment
1) Refraction: Waves are bent due to density differences
2) Reflection: Light waves bounce off of materials
3) Scattering: Waves are reflected and refracted in all directions
Explanation
4) Transmitted: Light waves are able to pass through
5) Absorbed: Light waves are taken into the material and turned to heat
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!!!!!!
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
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
3) Radiation:
Material:
The transfer of energy in the form of waves
No medium necessaryThe more energy an object has the more it gives off!!!
Eureka
Transformation of Mechanical Energy
Mechanical Energy: The total kinetic and potential energy in a system
Kinetic Energy: The energy of motion
Potential Energy:
Mass and velocity
Factors of P.E.:
Stored energy
Factors of K.E.:
Mass and position
Transformation of P.E. to K.E.
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 ????
Greenhouse Doom and Gloom
Temperature and Heat
Kinetic theory of matter: All matter is made of atoms that are moving
What is the relationship between kinetic energy and temp.?
Temperature: Average kinetic energy of a system or object
Direct
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!!!!!!!!!
Heat Energy and Changes in State
Melting: Solid to liquid
Sublimation:
Freezing: Liquid to a solid
Solidification: Liquid to a solid
Evaporation: Liquid to a gas
Condensation: Gas to a liquid
Solid directly to a gas
Precipitation: Gas directly to a solid
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 increasesWater being liberated (2260J/g used) During Vaporization:
100 to 200: Temp. of gaseous water increasing
Earth’s Energy Supply
Most Intense:
Solar Energy
Visible and Ultraviolet
Shortest wavelength (UV=sunburn)
Wave lengths:
Nuclear FusionWhat Produces Solar Energy:
Secrets of the Sun
Earth’s Own Energy
1) Remains from when earth first formed
2) Materials that are under extreme pressure
3) Radioactive decay of elements
Overwhelming