Helicopters

Sycamore trees and maple trees; you know, those ones that have leaves which turn such beautiful colours at this time of year?

Well they also have terribly 'clever' seeds. 

We found a few such seeds outside this morning, thanks to one or two keen hunters!

Luckily they found enough for us so we could all take a really close look at them. 

When we held one up to the window, we noticed that there was a wing-like part where the light came through as well as a darker, heavier part.  Tatiana suggested that the dark part was the seed.  And to prove it, she helpfully dug one out to show us (and which, at Tommy's insistence, we will, at a later stage, squish to see if our theory that all seeds contain oil is true; thanks for reminding me, Tommy!)

We showed with out hands how we thought the seeds would travel through the air; and amid wildly flailing arms and in no little danger of having an eye put out, we decided that perhaps the best way to find out would be actually to let one go.  From on top of our chairs.

And sure enough, they spun; round and round and round.

Now look carefully.  Which part of the seed hits the ground first?  Is it always the same part?  What about if you let go of the seed 'upside down'?  Not to worry if you can't tell (they do move rather fast!); just remember these questions for later.....

Now, let's have a go and see if we can make ourselves a twirling sycamore 'seed'.  With paper, scissors, a ruler and a paper clip.

First, take a rectangle of paper.  Rule two straight lines almost right the way across.....

and then snip along the lines, making sure you stop before you end up with three separate strips of paper!

 

Now, imagine that the paper clip is the seed, which needs to hit the ground first (maybe to help it dig itself into the ground?) and see if you can fold the paper in such a way to make the whole thing spin; round and round and round.  Where will you put the paper clip?

Think about that helicopter; the 'arms' or rotor blades.  How will you fold the paper so you get 'rotor blades' that will spin?

When you have decided, test it out.  This time (as long as you promise not to tell) you can get up onto your desks before you let go.

After more than a few not-quite-got-its, suddenly the room rang with shouts and whoops of success (sorry MissKate next door in the Library!)

Snap, snap, snap goes the motor-drive.....

and I just about caught one in action!

 

A(n almost) final question.  If I hold my paper sycamore seed upside down (with the 'seed', or paperclip uppermost) what will happen?  What part will hit the ground first?

Megna's hand shoots up.  "I think it will flip over so that the paperclip hits the ground first," she suggests.

And why do you think that Meghna?

"Well, because the paperclip is the heaviest part and that will hit the ground first, so it will turn over," she explains.

And do you know what?  She was right.  Because we tested it.  Three times.

And you can't say fairer than that.

Final question.  Think badminton.  Think shuttlecock (or 'birdie').  Which bit of the shuttlecock; the light feathery part or the heavier rounded part, do you always (try to) hit with your racket? 

How is a shuttlecock like a sycamore seed?