Transcript Convection and the Mantle

Heat Transfer
 Heat always moves from a warmer place to a cooler
place.
 Hot objects in a cooler room will cool to room
temperature.
 Cold objects in a warmer room will heat up to room
temperature.
Question
 If a cup of coffee and a red popsickle were left on the
table in this room what would happen to them? Why?
 The cup of coffee will cool until it reaches room
temperature. The popsickle will melt and then the
liquid will warm to room temperature.
Heat Transfer Methods
 Heat transfers in three ways:
 Conduction
 Convection
 Radiation
I. Types of Heat Transfer
Three Types:
1. radiation- transfer of energy through space. Ex: sun
warming a metal slide.
2. Conduction- transfer of energy when materials are
TOUCHING.

Ex 1: you’re touching the slide and getting burned.
 Ex 2: Pot of hot soup on stove. There is a spoon that
has been left in the soup. The eye of the stove
touches and heats the pot, the pot touches and heats
the soup, the soup and pot touches and heats the
spoon. You touch the spoon and the heat is
transferred to you.
3. Convection- transfer of heat through movement of
currents.
a. hot air and water/fluids rise b/c they are less dense.
They do not have as many molecules in them and that
is why they are lighter and rise.
b. cooler air, water and fluids sink b/c they are more
dense. They come close and have more molecules in
them so they sink.
II. Convection Currents- The heating of a fluid due to
currents: Heating, Rising, Cooling, and Sinking.
a. Heat from the core and mantle causes convection
currents in the mantle.
b. These convection currents cause Earth’s magnetic
field and the movement of Tectonic plates. The force
of push causes plates to move apart( diverging-causes
volcanoes). The force of pulling caused plate to move
together (converging- causes mtns).
Water movement
Cools at the
surface
Cooler water
sinks
Convection
current
Hot water
rises
Youtube- warm water rises, cold
water sinks
 http://www.youtube.com/watch?v=bN7E6FCuMbY
 Air rising and sinking
 http://www.youtube.com/watch?v=ZPErStqSSMk
Interactive site
 http://www.wisc-
online.com/Objects/heattransfer/default.aspx
Heat Transfer-united streaming
Be the teacher
 Explain the difference between radiation, conduction
and convection.
 With the explanation of what it is, also give examples
for each one.
Videos and songs
 Mr. Parr Heat transfer song-
http://www.youtube.com/watch?v=wr8Z4SCETPs
 Bill Nye- Heat
 http://www.youtube.com/watch?v=QGyEwNIQUSU
Homework
 Complete the Heat Transfer ws.