Trying building a device to measure how fast the wind is blowing in this SciGirls engineering activity. You may have heard a weather reporter warn, "Wind gusts are up to 30 mph!" Scientists measure wind speed using a weather instrument called an anemometer, which relies on cups attached to freely rotating arms to catch the wind and make the arms spin. The device then records the number of revolutions in a given time period and translates this into miles per hour (mph).
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