convection currents and the mantle objectives: –explain how heat is transferred –identify what...
TRANSCRIPT
Convection Currents and the Mantle
• OBJECTIVES:– Explain how heat is transferred– Identify what causes convection currents
Radiation
• The transfer of energy through empty space
• Examples:
-Sunlight
-Open flame
Conduction• Heat is transferred by
direct contact of particles of matter
• Heat travels from hot to cold
• Examples:– Hot frying pan, Fire poker
stick
Convection• The movement of a fluid,
caused by differences in temperature and density, that transfers heat from one part of the fluid to another
• Examples: -Heating water-Mantle in the Asthenosphere-Air --wind
Checkpoint-1
• What are the three types of heat transfer?
ANSWER-1
• RADIATION
• CONDUCTION
• CONVECTION
Checkpoint-2
• Describe how convection currents form?
ANSWER-2• The heating and cooling of a fluid changes in a
fluid’s density, and the forces of gravity combine to set convection currents in motion.
Checkpoint-3
• In general, what happens to the density of a fluid when it becomes hotter?
Answer-3
• In general, when a fluid is heated, its density decreases. --i.e.steam and ice
Checkpoint-4
• What happens to convection currents when a fluid reaches a constant temperature?
ANSWER-4
• When a fluid reaches a constant temperature, the convection currents stop.