How Do You Use an Anemometer?

Ever seen a flag flapping in the breeze and wonder to yourself how fast the wind must be to keep that flag straight out like that? There is one way to determine the speed of wind and it doesn't even require a fast computer to figure to the calculations. All you need is a ridiculously simple device known as an anemometer.
An anemometer is meteorological device that calculates the speed of wind. The amazing thing about this device is that every year they are made by the hundreds of thousands by elementary school children to make in science class while they are also used by every weather forecast in the country. Simple but effective.

Difficulty:

Easy

Instructions

Things You'll Need

• Anemometer Stopwatch or wristwatch

1. Understand that an anemometer essentially works by getting the wind to spin around three to five small plastic cups. The secret to learning how to use an anemometer to figure out wind speed lies in observing, paying attention and doing some calculations of your own.

2. In order to use an anemometer the ideal position for the device is at least 4 feet above the ground. It is also equally important to place your anemometer away from wind obstructions like buildings or trees. That way you can be sure to get an entirely accurate reading.

3. Keep your eye on the target cup and watch follow it as it revolves. The anemometer will have five cups and one of them will be of a different color so that it can be followed more easily as it revolves. Start the stopwatch and count how many times the target cups goes around in a minute. Record this number and then repeat two times, making sure to record the number of the times the target cup revolves.

4. Take the three readings and divide by three. The resulting number represents the average revolutions per minute. Although the actual wind speed of an anemometer is dependent upon its size, generally speaking every ten revolutions per minute is equal to one mile per hour.