Cup anemometers are simple instruments used by meteorologists to measure wind speed. This set of instructions will guide you through the process of making a very simple anemometer using some common household products.
Step 1: Materials needed
5 3oz. paper cups
1 pencil with eraser
1 push pin
1 pair of scissors
Step 2: Making the central hub
Using a pair of scissors poke 4 evenly spaced holes around the edge of 1 cup. These holes should all be the same distance away from the edge of the cup. WARNING the pair of scissors are sharp be careful not to poke your fingers when making holes.
Step 3: Adding the spokes
Insert the straws through the holes you just made so that the straws overlap in the center of the cup.
Step 4: Adding a bottom hole
Make a hole in the bottom of the cup at the very center. Make sure that the hole is the size of your pencil.
Step 5: Creating the stand
Insert the pencil through the hole in the bottom so that the eraser is touching the intersection of the straws.
Step 6: Adding the push pin
Poke your push pin through the two straws and into the eraser in the pencil.
Step 7: Making the outer cups
Using the scissors make two holes in the remaining 4 cups. Make sure that these holes are opposite of each other and are the same distance from the lip of the cups.
Step 8: Adding the outer cups
Place the onto the straws by threading the straws through the holes you just made in the cups. Position the cups so that the opening of one cup faces the bottom of the one before it.
Ten turns in one minute is equal to 1 mph of wind speed. Marking the bottom of one cup will aid in counting the revolutions.