Buoyancy in water
In this activity, students make a Cartesian diver to demonstrate the relationship between volume, mass and density. A similar principle is used in Argo scientific floats.
By the end of this activity, students should be able to:
describe some of the factors that affect what makes an object float or sink
understand how volume, mass and density are related
understand how Argo floats rise and sink in the ocean.
How Argo floats rise and sink
Dr Phil Sutton explains how the buoyancy of an Argo float is controlled to make it rise or sink.
Download the Word file for:
introduction/background notes
what you need
what to do
extension ideas.
Related content
Explore the big ideas that underpin floating and sinking in the article Building Science Concepts: Floating and sinking.
Activity ideas
Temperature, salinity and water density – use this activity to help your students visualise differences in water density.
Floating eggs – students investigate water density by floating an egg in freshwater and saltwater.
Investigating seawater – students investigate some of the properties of seawater.
