The Movement of Heat

1
The Movement of Heat

• Students will be able to describe how heat moves.

2
Journal

• Make a list of appliances that operate on the
  premise of moving heat.

3
Vocabulary

• Convection
• Conduction
• Radiation

4
Heat

• Heat is the flow or movement of energy.
• Heat spontaneously flows from areas of high
  temperature to areas of low temperature.

5
Heat

• Heat moves from one place to another three ways
  conduction, convection, and radiation.

6
Conduction

• Conduction is the movement of heat through a
  substance (or between substances) in contact with
  each other.

7
Conduction

• Are there any appliances that use conduction to
  move heat in your home?

8
Conduction

• Conduction is involved when heat travels from the
  burner to a metal pan on the stove. In a home,
  insulation is used to minimize heat movement by
  conduction.

9
Convection

• Convection is the movement of heat by the actual
  movement of a heated gas or liquid.
• For example, warm air (or water) is less dense
  than cooler air (or water) and therefore rises,
  while cold, more dense, air (or water) falls.

10
Convection

• Can you think of any instances when convection
  has occurred?

11
Convection

• In homes, a special case of convection known as
  "infiltration" occurs when air moves into and out
  of the home through cracks and other openings.
• Convection also causes hot air balloons to rise.

12
Radiation

• Radiation is the movement of heat away from an
  object by means of "electromagnetic waves" or
  "infrared" rays. This process involves only the
  molecules of the substance radiating the heat.

13
Radiation

• What are some instances of radiation?

14
Radiation

• Standing next to a campfire or feeling the heat
  from a oven are examples of radiation.
• The heat of the sun is also transferred via
  radiation.