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Have fun with the cartesian diver experiment

Suitable For

Grade 4



Time Required

 <12 Hours



What’s it about?

Water, similar to air, is a fluid. According to Pascal’s principle: when a force is applied to one point of a fluid in a closed container, the force is transmitted equally to all parts of the fluid. Try the following science experiment to see Pascal’s principle in action:

Topics covered

Pressure, Cartesian diver, Pascal’s principle

What will I need?


Procedure (Method)

Unfortunately, this section is only available in the e-book version of the project.

How does it work?

Unfortunately, this section is only available in the e-book version of the project.

This science experiment works according to Pascal’s principle. When the bottle is squeezed, the pressure inside the bottle is increased. The pressure inside the eyedropper also increases and you can actually see the water level rise inside it.

When the water level inside the eyedropper rise, the remaining air inside it is squeezed into a smaller space. This pressure makes the eyedropper heavier that the water around it, and it sinks or ‘dives’ down like a diver in the ocean. When the grip on the bottle is relaxed, the pressure inside the bottle and eyedropper decreases, and the water level returns to its original level making the eyedropper lighter again. The eyedropper then starts to rise to the surface like a diver coming up for air.

Like the sound of it?

Why not check out the full worksheet in one of our popular e-books?

This particular science project can be found in any of the following Experiland e-books:

Experiland e-books contain detailed steps, including illustrations, to complete the science projects from start to finish.

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A project introduction and background, complete listing of required materials, step-by-step instructions on how to carry out the project, why it works, learn more section, as well as a science glossary with all the relevant terms make up each of the all-inclusive science project worksheets in our e-books!

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