Convection currents in the air In Unit 2 of Module 3 - aquot;Energy and Changeaquot; you learned about convection currents in the air, i.e. thermals. This movement of the air is caused when air above the land heats up and rises as it expands and becomes less dense. Cooler air moves ... Fronts A front is a zone formed when a mass of cold air and a mass of warm air meet. ... it is usually heavy, but does not last long.
|Title||:||Science Matters Module 4|
|Author||:||Leana Eloff, Project Literacy (South Africa, James Whitelaw|
|Publisher||:||Pearson South Africa - 2002|