Saltwater Circuit
Students build a saltwater circuit, which is an electrical circuit that uses saltwater as part of the circuit. Students investigate the conductivity of saltwater, and develop an understanding of how the amount of salt in a solution impacts how much electrical current flows through the circuit. They learn about one real-world application of a saltwater circuit — as a desalination plant tool to test for the removal of salt from ocean water.
A working saltwater circuit. If the circuit conducts electricity, then we know salt is present in the water. If the circuit does not conduct electricity, then no significant amount of salt is present in the water.
Electrical engineers design and build small- and large-scale electrical systems. In the circuit design sub-discipline of electrical engineering, engineers use their knowledge of the conductivity of materials to design circuit boards that are used in cell phones, TVs, toaster ovens, computers, and uncountable other devices. Understanding the dangers and opportunities of mixing electricity and water helps engineers design for safety as well as creative measurement tools.
After this activity, students should be able to:
- Run an experiment.
- Collect and analyze data.
- Work as part of a team.