Wind Speed Task
An anemometer is a device that measures how fast the wind is blowing. As such, it is one of the most important instruments to be found in a weather station. The device you are going to build is a model of a real world 'anemo' that will give you an approximation of how fast the wind is blowing. You'll find instructions for making one below.
How to measure Wind Speed - Materials
N.B. For this experiment to be of scientific value you must use the following equipment:
- Scissors
- 4 small paper/plastic cups (like drinking cups)
- A colouring pen - any colour
- 2 strips of stiff cardboard - the same length
- Ruler
- Stapler
- Large drawing pin (thumb tack)
- Sharpened pencil with eraser on the end
- Blu tack or modelling clay
- A hard surface - cardboard or tile
- A watch with a second hand
Directions
- Cut off the rolled edges of the cups to make them lighter.
- Colour the outside of one cup with the colouring pen.
- Cross the cardboard strips so they make a plus (+) sign. Staple them together.
- Take the ruler and pencil and draw lines from the outside corners of where the cardboard strips come together to the opposite corners. Where the pencil lines cross will be the exact middle of the cross.
- Staple the cups to the ends of the cardboard strips; make sure the cups all face the same direction.
- Push the drawing pin through the centre of the cardboard (where the pencil lines cross) and attach the cardboard cross with the cups on it to the eraser point of the pencil. Blow on the cups to make sure the cardboard spins around freely on the pin.
- Place the blu tack or modelling clay on the hard surface. Stick the sharpened end of the pencil into the clay so it stands up straight.
Measuring the Wind
This anemometer cannot not tell the wind speed in miles per hour, but it can give you an idea of how fast the wind is blowing.
Every Friday at 11.30am from 19th February bring your “Anemo” outside and using your watch, count the number of times the coloured cup spins around in one minute. You are measuring the wind speed in revolutions (turns) per minute. Weather forecasters’ anemometers convert the revolutions per minute into miles per hour (or kilometres per hour).
Keep a record of the wind speeds you’re measuring for the week on the wall planner sent to your school and upload the data to the website.