Convection explained

The author begins with a quick definition of what convection is, followed by a hands-on demonstration of density using water and vegetable oil. After establishing that water is denser than v... See More

The author begins with a quick definition of what convection is, followed by a hands-on demonstration of density using water and vegetable oil. After establishing that water is denser than vegetable oil, the author suggests mixing the two liquids when they have different densities. After observing this phenomenon, the article discusses the two forces, gravity and buoyancy, that are acting on the water and oil. This leads further into bringing in the concept of pressure. To demonstrate pressure, the article introduces another hands-on. It keeps getting better as the author guides you through the complete development of the concept of convection. The strength of this article is its excellent concept development. There are several excellent figures and the introduction and use of scientific terms is easy for both the student and the teacher to understand. Starting with the definition, followed by several hands-on demonstrations to model each step needed to ensure that the student will understand the concept of convection, and concluding with real world/nature examples complete this article. Making it a “keeper” in any teacher’s files for teaching convection.

Density and Buoyant Forces

Robertson provides several hands-on activities to help students understand convection. When I used these activities in an in-service with elementary teachers, we were all appreciative of th... See More

Robertson provides several hands-on activities to help students understand convection. When I used these activities in an in-service with elementary teachers, we were all appreciative of the fact the materials were those that we could go to the store and purchase on our way home. The activities also helped solidify what density is in a way that is easily understood. Buoyant forces are also discussed using examples that are able to be understood by student and adult alike. This article has activities that would easily supplement any density curriculum.