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Heat Transfer. Heat transfer. Everything is made of molecules. When molecules gain energy they move faster and create more heat. (The faster the molecules move the hotter they are). Evaporation. Melting. Freezing. Condensation. Solid. liquid. Gas.
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Heat transfer • Everything is made of molecules. • When molecules gain energy they move faster and create more heat. • (The faster the molecules move the hotter they are) Evaporation Melting Freezing Condensation Solid liquid Gas Molecules move very slowly! They are close together. Molecules move faster and are more spread apart. Molecules move very fast! They are very spread apart.
Heat • Is the transfer of thermal energy from a hotter object to a cooler one until both objects are the same temperature. (You can not transfer cold or give someone cold) heat transfer video clip
3 ways that heat is transferred within the atmosphere Radiation Conduction Convection
The first method of heat transfer How does heat energy get from the Sun to the Earth? RADIATION ?
Radiation What creates electromagnetic waves? Video clip 1 video clip 2 Eureka start at 2:30 • The direct transfer of energy by infrared electromagnetic Waves. • Sun, fire, light bulbs
Pair Share • Partner A: What is radiation and where does it come from. • Partner B: What are three different things that create electromagnetic radiation?
Conduction • conduction video clip 1 • Eureka • The direct transfer of heat from one substance to another substance that is touching. Objects have to touch!!! Ironing Clothes Stepping on hot sand. That’s Hot
Conduction When you heat a metal strip at one end, the heat travels to the other end. As you heat the metal, the particles vibrate, these vibrations make the adjacent particles vibrate, and so on and so on, the vibrations are passed along the metal and so is the heat. We call this?
Pair Share: Partner A: Using the picture on the right explain the conduction process Pair Share: Partner B: Explain how the picture on the left is conducting heat.
Convection • convection video clip • Convection 2 • Convection- Eureka • The transfer of heat by movement of a fluid (liquids and gases). Cooking peas in water Blow Drying your Hair. Dryer OVEN
Water movement Cools at the surface Convection current Hot water rises Cooler water sinks
Heating the Troposphere Radiation, conduction and convection work together to heat the troposphere. • Radiation- heats the Earth • Conduction- Air near earth’s surface is warmed • Convection- the warm air molecules rise and transfer heat to the cooler air molecules. Eventually these molecules cool and sink back down to earth. This creates Convection Currents.
Radiation, Convection and Conduction work together to heat the troposphere. review of all 3 types Radiation Convection Current Conduction
Review Heat transfer from a hotter object to a cooler object until both objects are the same temperature. 3 types of heat transfer review3 types of heat transfer review, review 2 Music Review • Radiation – electromagnetic waves • Conduction – touching • Convection- through a fluid (liquid or gas) • All 3 work together to heat the troposphere but Convection causes most of the heating.