Wednesday, May 7, 2014

How to Make a Hovercraft


If you're on Pinterest, chances are good you've seen this activity. But for the few who haven't, get ready for some seriously cheap science fun. We made a hovercraft!



Supplies
An old CD that you no longer need
Glue gun and glue sticks
thumbtack
soda bottle screw top (you want one that's fairly deep)
latex party balloon

Assembly
Poke several holes in the plastic bottle top with the thumbtack.


Use a hot glue gun (Adults, please. No children. Those things are H-O-T) to apply a bead of glue to the edge of the bottle top and glue it to the center of the CD, over the hole. If necessary, apply a bead of glue around the cap to make sure it's totally secure.


You're almost done.

Now blow up the balloon. Twist the neck of the balloon to keep it inflated and pull the lip of the balloon over the edges of the bottle cap.


Ask your child to make predictions. Before we released the hovercraft, my son thought it would glide through the air more like a hot air balloon.

Let it Go
Set on a flat surface like a countertop or wood floor. Release the balloon and watch it glide along without any effort just over the surface.

Invite the child to form a hypothesis about why and how this works.


How it WorksThe force of the air that exits the balloon as it deflates goes through the holes in the bottle cap, pushes against the surface (floor or counter), and creates a cushion of air over which the CD glides freely.

14 comments:

  1. Superb. Love it--will have to try this with y daughter
    Cheers
    Dr Sonia

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  2. Awesome, fun hands-on learning. Like reusing items from the house! My kiddos will love this.

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  3. cool my mom put me on pentrest and i found this! it looks like a ton fun! XD lol

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  4. Mine doesn't work! Thoughts? It actually worked a little bit the first time I tried it, but hasn't since.
    One idea is the balloon falls to one side as the air goes out.
    I also tried covering up some of the holes, but same result - no hovering.
    Would love any thoughts or feedback on getting this to work. I wanted to use it as a makerspace project in my school library.

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    Replies
    1. Instead of poking holes in a lid, try using a pop-top water bottle lid. I've seen this on other sites. There may be more air exerted out all at once with this other lid, improving the effect. Good luck!

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  5. Would it work better with bigger holes or maybe a bigger one in the middle?

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    Replies
    1. yea that would be i good idea

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    2. It does work better with a hole in the center of the cap. I taught the children to put the balloon through the hole blow it up pull lip of balloon up so it does stop the hovering😊

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  6. More holes seemed to do the trick!
    Also putting a band of paper or cardstock in a circle around the neck of the balloon to keep it upright helps. Directions here: http://www.stevespanglerscience.com/lab/experiments/cd-hovercraft-sick-science/
    Thanks all!

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  7. It didn't work! Tried 9" and 12" balloons. A big disappointment.

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    Replies
    1. I'm sorry your experiment was a bust. Did you try some of the suggestions left in the comments above? I hope you'll give it a second chance as the effect is amazing.

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  8. Can't wait to try this with my first graders. Great prediction tool for our Force and Motion Unit. Thank you.😊

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  9. Multiple attempts. All fails. Disappointed. Tried covering holes. Bigger holes. All fails. Boo for this experiment. 3 disappointed grandkids was not the intended outcome.

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  10. Tried this today with nice success! Made two so that we could make and test our hypotheses by changing one variable at a time and then testing them side by side. We tried different lids, different # of holes in lids, and different sized balloons. The best combo we found was a pop-top dishwash detergent lid and a 12" balloon. Thanks for the inspiration!

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