Want to make a fun DIY toy that moves? This kinetic carousel spins wildly and demonstrates potential and kinetic energy.
- paper and carousel template (pdf)
- plastic lid – about 3″ diameter (peanut butter jar lids are perfect)
- wide rubber band (thin rubber bands won’t work!)
- paper clip
- clear tape
- plastic straw (cut a 3 ½” length)
- 2″ long plastic tube a 1″ diameter PVC coupling from the hardware store works well! If you want to repurpose something from home try one of the following:
- An extra wide straw cut down to 2”
- An empty tube of lip balm, center removed.
- drill & drill bit (adults only)
Note: You must use plastic tubing. Paper tubing i.e. paper towel rolls, will create too much friction with the plastic lid. It’s also important to make sure your tube is wide enough for the rubber band to twist and unwind.
- Print template on plain paper or cardstock. Color the carousel and top as desired.
- Cut the paper template along the bold lines. Fold along dashed lines. Set aside.
- Drill a ¼” diameter hole through the center of the plastic lid. (Adults only) If you don’t have a drill bit that large you can rotate the drill slowly as you make the hole to enlarge it.
- Thread your straw through the rubber band and knot. Pull the loose end of the rubber band through the plastic tube. If you are using a narrow tube you can push the band through the tube using a toothpick.
- Thread the rubber band though the hole in the bottom of the lid, thread a paper clip through the rubber band, and tape the clip to the inside of the lid.
- Wrap the carousel template around the plastic lid. Tape the paper together to form a circle, then tape lower part of the template to the bottom of the lid. Add the paper top to the carousel and secure in place with glue. Let dry.
How to Play with the Carousel
- Hold the center tube and the carousel top. You should be able to hold both at the same time with one hand. With your other hand, wind up the toy by twisting the straw and rubber band.
- Let go of the carousel. It should spin quickly! Wind it up and spin again.
- Make sure the rubber band is able to unwind. If your plastic tube is too constrictive the rubber band will get knotted up inside and be unable to twist.
- Sometimes you can wind up the rubber band too much, making it knotted and unable to unwind. In this instance flip the carousel over, let it unwind completely, then try winding it again.
- After a lot of winding your rubber band may begin to tear. If this happens replace the rubber band.
The Science Behind this Project
Kinetic Carousels demonstrate two types of energy: potential energy and kinetic energy.
Potential Energy is stored energy. When the rubber band is tightly wound it has a lot of energy, but until you let go, the energy is stored up waiting to be unleashed; we call this potential energy.
Kinetic energy is the energy of an object in motion. Once you release the top of the carousel, the rubber bands unwind quickly; this movement is kinetic energy.
Extend the Activity
- Experiment with different materials for the plastic tube. By varying the tube you will be able to see what materials and shapes work and what don’t. Try substituting a paper towel tube cut down to 2 inches. You’ll find that the paper tube and plastic lid create too much friction when they are in contact, and the carousel spins very slowly.
- Color the top with two primary colors. When you spin your carousel watch the colors combine for a moment into a secondary color!