# BRW Science Challenge Number 11

### Make a Spinner!

• CUT along the solid lines and FOLD along the dotted lines.
• PAPER CLIP the three folded pieces of the tail of the spinner.
• FOLD the two ‘wings’ of the spinner in opposite directions. Hold the spinner high up, let go and watch what happens!
• MAKE more spinners …. you could make different sizes, use different types of paper, use more paper clips or change the length of the wings.

WHAT DO YOU NOTICE?
What happens when you let the spinner go? Can you slow the spinner down? How?
What happens if you use different sorts of paper? Does tissue paper fall fast or slower than cardboard? What happens when you make the wings longer or shorter? What if you make a giant one? A tiny one?

TRY THIS OUTDOORS ….
Take your spinner outside. Make a target on the ground – you could do this by drawing a circle on a large sheet of paper, or you could use a big shallow bowl. Hold your spinner up and drop it, trying to get it to land on your target. Have ten goes and count how many times you hit the target. Try moving the target to a different place outside and see if your score increases or decreases.

WHAT DO YOU NOTICE?
Where outside is it easiest to get the spinner to hit the target? Why do you
think that is? What happens if you make the target bigger or smaller?

WHAT IS THE SCIENCE?
The paper spinner spins as it falls. When it starts its fall, the air pressure under the wings increases (air resistance). This causes an upward force underneath the wings which slows the spinner down. The increased pressure also causes a sideways push on the vertical part at the top of the spinner (where the pink dot is). The same thing will be happening diagonally opposite under the other wing (dotted pink line), which causes the spinner to spin. The faster the spinner falls the greater the sideways push, and so the more it spins.