Hovercrafts Aren't Just Science Friction Activity
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Recommended Grade Level(s):
Appropriate for: Elementary and Middle School
Time Requirements:
Activity Time: 30–45 minutes
Teaching Topics & Concepts:
• This activity covers engineering design, technology, forces, motion, surface, and math.
• Students gain first-hand experience in Newton's laws of motion.
Materials:
• A balloon
• An old CD
• Dish soap cap
• Hot glue gun/stick (or use packing tape and scissors)
Background
Engineers use the concept of friction to design moving objects. Depending on the application, friction may be a good or a bad
thing. So, engineers design materials to either increase or reduce friction. Car breaks, athletic cleats, and snow tires are all designed
to create more friction. Car oil, curling sweepers, and ball bearings are examples of ways we reduce friction between moving parts,
so they run smoothly. A skydiver's parachute, a flying airplane, and riding a bicycle demonstrate the impact of air resistance. Use the
completed hovercrafts to investigate and discuss these concepts.
Procedure:
1. Run a generous ring of hot glue around the bottom edge of your dish soap cap
2. Quickly press it onto the center of the CD, over the hole. Create a good seal to keep air
from escaping.
3. Let the glue cool until it has hardened
Alternate: Using packing tape, securely tape the bottle cap onto the CD. When you tug on
the cap gently, there should not be a gap between the cap and the CD.
4. Slip the balloon over the cap.
5. With the balloon over it, pull the cap upward.
6. Blow up the balloon through the hole on the other side of the CD.
7. Press the cap down until you're ready to let the hovercraft go.
8. When you're ready to hover, put the craft on a smooth surface, and pop the top open
so the balloon can deflate underneath through the CD's hole.
Safety
• Hot glue can burn, so it requires adult supervision when students use it. Or an adult can do the
gluing for the students.
!