Prior
Knowledge:
*What causes the
metal handle of a spatula to get hot if you leave it in a pan?
(conduction)
*Why do your feet hurt after walking barefoot across the beach on a hot day? (because your feet become hot because of physical contact with the hot sand)
Definition of Conduction:
Energy transferred through matter from particle to particle; most effective in solids; the movement of heat through a substance by direct contact of molecules. Molecules are always in a state of constant motion. The faster the molecules are moving, the more heat energy is transferred. Because all matter is made of molecules, conduction can take place in solids, liquids and gases. Substances, such as metals, that conduct heat the best are called conductors. Substances that do not conduct heat easily are called insulators. Examples of insulators would be glass, wood, plastic and rubber.
Activity 1
Materials: metal cans; hot water; ice water; hot plate to heat water
1. Fill one container with hot water and the other with ice water.
2. Hold each can in your hand.
* What causes your hand to get hot?
*What causes your hand to get cold?
Activity 2
Materials: nail, candle, match
1. Hold a nail in the flame of the candle.
*Explain why the flat end (head of the nail) gets hot.
