Cartesian Diver Prompt

1.      Build a Cartesian diver as per the teacher’s instructions.

2.      Once the diver is working properly, observe the diver carefully.

3.      Write a paragraph describing how the diver works.  Refer to the rubric for everything the paragraph should include to be well written.

4.      Include the following terms in your explanation: gas(es), pressure, volume, Boyle’s law, density and Archimedes’ principle of buoyancy.

5.      A labeled drawing of the diver system should accompany the paragraph.

 


A Cartesian diver is a simple device to construct.

The materials needed include:

1.      an empty, clear plastic bottle with cap,

2.      a Thin-stem pipette,

3.      a small hex nut, and

4.      a rubber band.

Directions for construction:

1.      Partially cut the stem of the pipette off.

2.      Slip the hex nut onto the stem of the pipette.

3.      Wrap the rubber band around the stem several times to prevent the nut from coming off.

4.      Fill the pipette bulb a little more than half full of water.

5.      Fill the plastic bottle completely with water.

6.      Test the diver in the bottle or a cup filled with water.  It should just barely float.

7.      If the diver sinks, remove some of the water and increase the size of the air bubble in the bulb.

8.      If the diver floats too high, release some air and add more water to the bulb.

9.      Place the diver into the plastic bottle and screw on the cap.

10.  If the amount of air and water in the diver bulb is correct, simple squeezing the bottle will make the diver sink.

11.  Releasing the pressure will allow the diver to rise.

 



Cartesian Diver Paragraph Rubric

Focus and Purpose

Strong (5)

Developing (3)

Not Yet (1)
  • Information is complete and accurate.
  • All arguments are scientifically supported.
  • The information is correct.
  • The relationships between ideas correctly describes the way in which the diver functions.
  • Information is clear but not complete.
  • Arguments are correct but not supported.
  • There are one or two mistakes in describing how the diver works.
  • The relationship between ideas has flaws.
  • Information is incomplete or unclear.
  • Arguments are not supported.
  • There are major errors in understanding and describing how the diver functions.

Style, Tone, and Terminology

Strong (5)

Developing (3)

Not Yet (1)
  • The information is written at an appropriate level for a peer to understand it.
  • The author uses the 3rd person passive voice (no personal pronouns: I, we, you, etc.)
  • All required vocabulary terms are used correctly
  • There is no unnecessary information.  Scientific language is used throughout.
  • An accurate, labeled drawing of the diver accompanies the explanation.
  • The language is too complex or too simple.
  • The author uses one or two personal pronouns.
  • One or two vocabulary terms are used incorrectly.
  • Some unrelated information is present.  Some unscientific language is used.
  • An unlabeled diagram is present.
  • The writing is not in paragraph form and is not in sufficient depth.
  • The author uses personal pronouns frequently.
  • One or more terms are missing from the explanation or more than 2 terms are used incorrectly.
  • The author uses little or no appropriate scientific language.
  • No drawing is present.