SCIENCE CONCEPT:
- Convection current is heat transfer from or to something that can flow. Anything that flows
is called a fluid. Fluids can transfer heat by convection. This movement of the air when part
of it is heated sets up what we call a "convection current".
STUDENT OBJECTIVE:
- The student will observe how wind moves in the atmosphere by constructing a convection
current box.
OVERVIEW:
- In this activity, the student will construct a convection current box by using an empty
aquarium. Students will use ice to represent cold air and lamps to represent warm air. Upon
lighting a match, this will form a cloud, the warm air rises as the cool air sinks. Movement is
created causing wind.
TEACHER TEXT:
- As air warms its molecules spread out. When there's some space between them, the molecules
become less dense. This means the warm air weighs less for the amount of space it is taking
up. The cooler air gets pulled down by gravity because it weighs more for the amount of
space it takes up. It forces the warm air up. Some of the cooler air at the bottom becomes
warmer and some of the warm air at the top cools. This cool air sinks and pushes up the
warm air. This constant switching is called a natural convection
current.
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PREPARATION TIME:
- 20 minutes.
LESSON TIME:
- 60 minutes.
TEACHER PREP:
WORDS TO KNOW:
- convection current
- contract
- expand
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