Convection currents t notes

CONVECTION CURRENTS & THE MANTLE


1. Heat Transfer - The movement of energy from a warmer object to a cooler object

Why will this girl burn her hand if she touches the pot?


2. Types of Heat Transfer - Radiation, Conduction, and

Convection.


Heat travels from one object to another. When your warm hand touches the ice cube, some of the heat goes from your hand to the ice and begins to melt it.


3. Radiation – the transfer of energy through empty space (ex: sunlight); takes place with no direct contact between a heat source and an object


4. Conduction – heat transfer by direct contact of particles of matter (ex: spoon getting hot in pot)


When you are roasting marshmallows, the stick can heat up and burn your hand when you touch it due to conduction.


5. Convection - heat transfer by the movement of a heated fluid; heated particles of fluid begin to flow, transferring heat energy from one part of the fluid to another.


6. Density – A measure of how much mass there is in a volume of a substance (compactness); decreases as particles are heated because they occupy more space; increases as particles cool because they are closer together

Which object is more dense? In other words, which object has more mass in the given volume?


7. Convection Current – The flow that transfers heat within a fluid; set in motion by the heating and cooling of the fluid, changes in the fluid’s density, and gravity; continues as long as heat is added


How can you use convection currents to explain why warm air rises?


As the hot air rises, the cool air rushes in underneath to fill the space. As the cool air warms up, it also rises, and air currents are created. The currents make the convection curler turn.


8. Convection in the Earth’s Mantle – Heat is from Earth’s core and from the mantle itself; rises into the asthenosphere


http://www.windows.ucar.edu/cgi-bin/tour.cgi?link=/sun/Solar_interior/Sun_layers/Convection_zone/sun_conv_big_jpg_image.html&sw=false&sn=235311&d=/sun/Solar_interior/Sun_layers/Convection_zone&edu=elem&br=graphic&cd=false&fr=f&tour=

Convection currents t notes

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