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.
Download the Word file for:
- introduction/background notes
- what you need
- what to do
- extension ideas.
Explore the big ideas that underpin floating and sinking in the article Building Science Concepts: Floating and sinking.
Read the articles Ocean salinity and Ocean density to learn about the vital role salinity and density play in ocean currents and heat circulation.
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.