How Do You Make A Spinning Cartesian Diver?
• Bend a straw into a “J” shape. • Cut the straw so that the length of the left and right is same. • Insert the straw through the washer so that the washer rests on the bendy part. • Pinch the ends together with pliers. • Hold up a flame to the ends so that they are sealed together. • Make two holes with a pin, as shown in the images. • Drop the straw into a glass of water. • Adjust the buoyancy by squeezing it so that the straw sucks up water through the pin holes. That’ll make it sink a little. You want it so that about 5-10mm of the straw is barely above the water. • Repeat all of these steps to make a second Cartesian diver. • Put both divers in a bottle of water. • Screw on the bottle cap tightly. The seal must be airtight. Grasp a bottle and experiment with squeezing it and loosening your grip. When this movement is repeated, the straws will spin as they go up and down.
