How do I Rate Wind Speed?
- 1). Cut the rolled edges off the plastic cups; this makes the cups become lighter. Do this for all four cups, including the red one.
- 2). Staple the cups to the cardboard. Cross the cardboard pieces to make a plus sign and staple each cup to the bottom end of each piece of cardboard. All the cups must face the same direction.
- 3). Place the eraser end of a pencil in the middle of the cardboard pieces. Lift the cardboard cross with all four cups up and estimate the approximate middle of the cross.
- 4). Push a push pin through the top of the cardboard pieces so the pin penetrates the cardboard and into the eraser end of pencil. The device should resemble an umbrella, with the pencil holding up horizontal cardboard pieces with each end having cups stapled to the bottom.
- 5). Anchor the free pencil end in the molding clay until the pencil cannot move. The molding clay gives the device an anchor so it can be set up anywhere. Now the device is a makeshift anemometer.
- 6). Place the anemometer on a high surface. It needs to be at a height where wind will easily hit it. The top of a porch or near an open windowsill or balcony are effective locations to measure the wind. If a student or child is making the device, make sure adult supervision is available.
- 7). With your stop watch, notice how long it takes for the red cup to circle around the anemometer. Record the seconds it takes for each revolution. You can also set a time frame--for example a half hour--and record the number of revolutions the red cup makes on the anemometer. Both measurements serve as tools to measure how fast the wind is moving within a set time span.
Building the anemometer
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