1. Chapter 7 Chapter 4 in Old Textbook – pg. 115
Plate Tectonics

2. Chap 7, Sec 1A (Convection Currents and the Mantle)
Objectives:
How is heat transferred?
What causes convection currents?

3. WHAT IS HEAT?!

4. SO…. WHAT IS HEAT?!
Heat is one property that ALL molecules have……these molecules move to create heat (thermal energy)

5. Tech Terms:
heat transfer – when energy moves from a warmer object to a cooler object (water in ice cube tray transfers heat to inside of freezer).

7. radiation – heat transfer that requires NO direct contact between a heat source and an object.
conduction – heat transfer by direct contact of molecules of matter.

8. convection – heat transfer by movement of fluid (liquid or gas).

9. convection current – created when there are differences in temperatures and densities within fluids (liquid or gas).
The heating and cooling of the mantle material (which changes its density) and the force of gravity are what powers the convection currents.