Name ______Period #______
Objective: To create an anemometer using the materials supplied in class.
Materials: 5 – three ounce Dixie Cups 2 – soda straws
1 – whole punch 1 – thumb tack
1 – marker 1 – ruler
1 – stapler 1 – pencil with eraser
Procedure: Students must follow the steps below carefully and accurately.
Step 1: Please take one Dixie cup from the five you have received. Using your ruler and the marker, please mark a dot ¼ of an inch from the top rim of the cup.
Step 2: Using that same Dixie cup, take your hole puncher (if there is one at every table) and punch out the dot that you just marked. You should now have one Dixie cup with a hole punched in it.
Step 3: Repeat steps 1 – 2 for three other Dixie cups. This will give you a total of four Dixie cups with a hole punched out at the ¼ inch mark from the top rim of the cup.
Step 4: Take one straw and push it through the hole of one of the Dixie cups that you punched a hole into.
Step 5: Using that same cup with the straw in it, bend the straw at the end creating a flat “L” shape with the straw.
Step 6: Decide which way you want your Anemometer (cups) to point. See the picture on the next page. Once you have decided on your direction, take the stapler and staple the “L” end of the straw to the Dixie cup.
Step 7: Repeat steps 4 – 6 one more time. This means you will have two Dixie cups with a straw through and stapled onto it.
Step 8: Take the unused Dixie cup and on the bottom measure the center of the cup with your ruler. Mark your center point with your marker by placing a dot at that location.
Step 9: Measure ½ of an inch down from the top rim of that same cup (dot on bottom) and using your marker, mark a dot at that spot. You will need to mark three other dots at the ½ inch mark equally spaced throughout the top of the Dixie cup. This means, you should have 4 dots in total around the top rim of the cup all at the ½ inch mark.
Step 10: Hole punch all of those dots out of the Dixie cups
Step 11: Take one of your two Dixie cups with the straws stapled inside of them. Push the unused end of the straw through one of the holes of the Dixie cup with the four holes. Continue to push the straw through to the opposite side of the cup.
Step 12: Take one of the Dixie cups with the hole ¼ inch from the top and push the straw from Step 11 through this cup (it should be the end of the straw that is hanging out of the cup with four holes).
Step 13: Turn your cup that you just put through that it matches the direction of your “L” straw cup (look at the other end of the straw you are holding).
Step 14: Bend the end of the straw to create an “L” and staple it onto the cup. You should now have two cups stapled to the straw moving in the same direction.
Step 15: Repeat steps 11 – 14 until you have four Dixie cups attached to one center cup (the one with four holes around the rim) all moving in the same direction.
Step 16: See a parent or guardian for help making the center hole underneath your Four Hole Cup.
Step 17: Push your pencil – Eraser end first up through the bottom of the cup until you reach your straws.
Step 18: By yourself or with a partner, push the thumb tack through the two straws and into the eraser top. Please see a parent or guardian for help on this if you are uncomfortable in any way.
Your design should look like this. If it does not…you did something wrong.
Test your model: Go outside to test your model. Some forces are being ignored including drag and friction for this basic illustration, so the velocity at which your anemometer spins is not the same as wind speed.
Explanation: An anemometer is useful because it rotates with the wind. To calculate the velocity at which your anemometer spins, determine the number of revolutions per minute (RPM). Next, calculate the circumference (in feet) of the circle made by the rotating paper cups. Multiply your RPM value by the circumference of the circle and you will have an approximation of the velocity of at which your anemometer spins (in feet per minute). Your anemometer doesn't need to be pointed in the wind for use.
Extra Credit Due Date: Friday, March 13, 2015
Value: 5 Points added to your lowest TEST grade for MP #3
· Please take/print a picture of you and your model and glue or tape it onto a blank sheet of paper. Then, write in your math calculations on the bottom of the paper, put your name on the sheet and turn it in during school hours.