Studying the Cartesian Diver 2.25

Written by David Green.

It was a classic science experiment that Morenci eighth grade students tackled last week in Mr. Hoffman’s class. cartesian.diver2.jpg

Taking principles developed by Greek philosopher Archimedes more than 2,000 years ago, students constructed their own Cartesian Diver to study the relationship between buoyancy and density.

The Cartesian Diver is named for 17th century French scientist René Descartes although his connection to the experiment has never been found. A more correct name might be the Maggiotti Diver since it was Galileo’s student Raffaelo Maggiotti who claimed to have invented the device.

In the modern version of the experiment, students take a plastic pipette (medicine dropper) and thread a metal nut onto the stem. This is the diver.

The diver is partially filled with water—just enough so it barely floats upright in a container of water.

The diver is inserted into a soft drink bottle of water and the bottle is capped.

Now the fun begins.

When the bottle is squeezed, the diver dips down deeper into the bottle. When pressure is released, it quickly rises back to the top.

Why does it happen? Added pressure on the bottle compresses the air in the diver. It becomes more dense and sinks in the water.

It’s the same principle fish use to sink or float when a muscle squeezes or relaxes around an air sac. Similarly, submarines can be made to rise or sink by pumping water in and out of tanks.

  • Front.splash
    Water Fun—Carter Seitz and Colson Walter take a fast trip along a plastic sliding strip while water from a sprinkler provides the lubrication. The boys took a break from tie-dyeing last week at Morenci’s Summer Recreation Program to cool off in the water.
  • Front.starting
    BIKE-A-THON—Children in Morenci’s Summer Recreation Program brought their bikes last Tuesday to participate in a bike-a-thon. Riders await the start of the event at the elementary school before being led on a course through town by organizer Leonie Leahy.
  • Front.drum
    on your mark, get set, drum!—Drew Joughin (black shirt), Maddox Joughin and Kaleea Braun took the front row last week when Angela Rettle and assistants led the Stair District Library Summer Reading Program kids in a session of cardio drumming. The sports and healthy living theme continued yesterday with a Mini Jamboree at Lake Hudson State Park arranged by the Michigan Department of Natural Resources. Next week’s program features the Flying Aces Frisbee show.
  • Front.art.park
    ART PARK—A design created by Poggemeyer Design Group shows a “pocket art park” in the green space south of the State Line Observer building. The proposal includes a 12-foot sculpture based on a design created by Morenci sixth grade student Klara Wesley through a school and library collaboration. A wooden band shell is located at the back of the lot. The Observer wall would be covered with a synthetic stucco material. City council members are considering ways to fund the estimated $125,000 project and perhaps tackling construction one step at a time.
  • Front.train
    WRECKAGE—Morenci Fire Department member Taylor Schisler walks past the smoking wreckage of a semi-truck tractor on the north side of the Norfolk and Southern Railroad tracks on Ranger Highway. The truck trailer was on the south side of the tracks

Weekly newspaper serving SE Michigan and NW Ohio - State Line Observer ©2006-2016