Wind is a form of kinetic energy, i.e. energy in motion. For centuries, people have used windmills to convert moving energy into mechanical forms to perform tasks such as grinding grain and pumping water. Let's learn how to make a pinwheel. We will see how a basic turbine works and how wind can create mechanical force.
- One square sheet of thick paper
- Scissors
- Sellotape
- Cup
- Thread
- Thread spool
- Thick, strong stick
- Two blocks of wood
- Wooden slab
- Pencils
- Glue
- Hair dryer
- Adult supervison
What you do
Creating the base:
- Take two wooden blocks. With the help of an adult, drill a hole through each block, big enough for the thick stick to pass through easily.
- Glue the blocks parallel to each other on the wooden slab, keeping a distance between them.
- Put the stick through the wooden blocks and string up the cup with the thread. Let the thread be longer than the length of the ground from the table.
- Wind up the thread on the stick in the space between the two wooden blocks.
Making the fan:
- Take the square piece of thick paper. Look at the pinwheel pattern (see below) for the following steps.
- Use a ruler to draw diagonal lines from corner to corner. Make a small mark along each line three fourths of an inch from the centre of the square.
- Cut along the diagonal lines towards the centre until you reach the three fourth-inch mark. Get the thick stick out through the centre of the paper.
- Fold the corners marked with circles on the pattern into the centre and tape the layers together on the stick. When all four "blades" are folded in the pinwheel, it is ready.
- Now, use the hair dryer perpendicular to the top of the pinwheel wind turbine. Notice how fast the stick rotates and pulls the cup upwards.
You can experiment and design the wind turbine using different materials and compete with your friends on whose turbine is the fastest.