Topsy’s experiments
A ring glider
How can you make a drinking straw fly? With the help of four physical forces!
What you’ll need
What you’ll need
- Paper, e.g., from an old brochure or magazine
- Paper drinking straws or wooden skewers
- Adhesive tape
- Scissors
- A ruler
How to do it
How to do it
1. Cut out two equally wide strips from the paper. One strip must be half as long as the other. For example: 13 × 3 cm and 26 × 3 cm.
2. Stick the ends of each strip together to make two rings, one large one small. Make sure that the ends of each ring overlap slightly.
3. Stick one piece of adhesive tape to one end of the straw.
4. Fix the straw flush to the inside of one ring. Make sure that the end of the straw does not protrude beyond the paper strip.
5. Attach the second ring to the other end of the straw. Adjust the ring so that it points in the same direction as the other one.
6. Ready! Hold the straw in the middle so that both rings are angled upwards, with the small ring at the front. Throw the glider forwards and upwards, as if it were a paper plane. What happens? Do the same thing with a drinking straw without rings.
Well spotted!
Well spotted!
When you throw a straw, it rotates around its own axis and quickly falls to the ground. But with the rings attached, it remains stable and glides a short distance.
What’s the secret?
What’s the secret?
Your ring glider is subject to four physical forces:
- Gravity: It pulls the glider towards the ground.
- Lift: Differences in air pressure between the top and bottom of the rings keep the ring in the air for longer and allow it to glide like the wings of an aircraft.
- Thrust: When you launch your ring glider, you “push” it in a certain direction, like the engine of an aircraft.
- Drag: When you launch the glider, the surrounding air is moved and carried along. This kind of friction takes energy away from your glider and eventually causes it to drop to the ground.
