Explore ideas about wind and air by designing and testing a wind-detecting device in a variety of wind speeds. How will your detector show the difference between calm, a breeze, and a gale?
Time: 20-30 minutes
Topics: wind, breeze, gale, design challenge
What You Need
- An electric fan, preferably one with multiple speed settings
- Assorted materials for building a wind detector, like:
- Wooden craft sticks
- Unsharpened pencils
- Pipe cleaners
- Tissue paper
- Crepe paper
- Fabric scraps
- Construction paper
- Coffee filters
- Paper clips
- Push pins
- Paper cups
- Brown paper bags
What To Do
1. Start by thinking or talking about some of your own experiences with wind. For example:
- What are some ways you know it is a windy day just by looking out the window?
- Have you seen anything in your yard or neighborhood that moves differently on windy days?
- How does wind affect objects differently?
- How can we detect how strong the wind is?
2. Do some research by looking at photos or video clips of real-world wind devices for inspiration, such as windsocks, weather vanes, anemometers, or pinwheels. Think about:
- Have you seen anything like this before? Where did you see it, and what did it do?
- What shapes are in this object? What different parts does it have?
- Which parts move in the wind? Which parts stay still?
- How would this object move differently in different wind speeds?
3. Do some more research by exploring the materials you collected. Predict how those various materials might move in the wind. Test your ideas by turning on the electric fan and holding the materials in front of it.
- Do they move differently if the fan is set to different speeds?
- How do they move if you blow on them gently with your breath instead of the fan?
- Which of these “wind” sources might represent a light breeze? Which is the best model for a strong, gale-force wind?
4. Now make a plan for your wind detector. Decide how your detector might show different speeds of wind. Sketch your plan, showing the different parts of the detector and what materials you will use.
5. Build time! Be sure to test your detector frequently while you build by holding it in front of the fan or blowing on it. Change your design based on what you see, and then test it again! Think about things like:
- How does your detector move in high speed winds or low speed winds?
- How could you change your detector, so it moves differently in low speed winds?
- What materials might move in high speed winds but not low speed winds?
6. As you refine the design for your detector, think back to your design criteria: does your detector show the difference between calm wind, a breeze, and a gale?
7. Take your detector outside and give it a try! Can you tell when the wind is calm, a breeze, or a gale?
One way to measure wind speed is by using a scale called the Beaufort Scale. It is a scale from 0-12 describing both wind speed in miles per hour, and also effects you can see outside, in case you don’t have a tool to measure in miles per hour. Level 0 is calm, when everything you see is still. Levels 2-6 are different strengths of breezes which can be seen by what’s moving on a tree, like only the leaves or branches. Levels 7-9 are the gale force winds where whole large trees move or branches break off. Levels 10-12 are storm winds, up to hurricane force, where lots of structures and trees are blown down.
To create new tools like your wind detectors, engineers use the engineering design process:
- Research – Find out what other people have already made or discovered related to the item.
- Gather requirements – List all the things the new item needs to have, be, or do in order to work correctly.
- Brainstorm and plan – think of lots of different design ideas and then choose the best one.
- Build and test – make a first version of the item and test it.
- Redesign and retest – keep changing, testing, and improving the design until it meets all the requirements as well as it possibly can.