Thermal Energy

1
Thermal Energy

• Conduction, Convection and Radiation

2
How Heat Travels

• Heat moves from ________ matter to ________
  matter.
• Heat moves in 3 different ways
• __________
• __________
• __________

warmer
cooler
Conduction
Convection
Radiation
3
Conduction

• Definition
• The transfer of __________ through a material by
  ___________ __________.
• Examples

heat
direct contact
A metal spoon gets hot quickly in hot cocoa
An iron heats up the material it comes in contact
with.
4
Heat transfer by Conduction

• Note that in metals, heat is transferred through
  free-moving electrons, and in other substances
  through moving atoms.
• images from http//www.bbc.co.uk/schools/gcsebit
  esize/science/aqa/energy/heatrev1.shtml

5
Convection

• Definition
• The transfer of heat in a __________ (gas or
  liquid) as a result of the ______________ of the
  fluid itself.
• Examples

fluid
movement
Boiling pasta in water.
Wind currents.
6
Heat transfer by Convection

• Note that the warm material rises, cools at the
  surface and then sinks in a circular pattern.
• animation from http//commons.wikimedia.org/wiki
  /FileConvection.gif

7
Radiation

• Definition
• The transfer of heat via __________________
  _________ through ___________ .
• Examples

waves
electromagnetic
space
The heat from the sun melting ice cream.
The heat from a campfire.
8
Review All Three
B.
A.
C.
9
Animations of Conduction, Convection and Radiation

• Teacher's Domain Animations
• Movie of convection in the sun
• Effect of heat on atoms