Here's a collection of optical illusions that are actually magic tricks and many
have free downloads so you can print out and do the tricks yourself. Let's get started.
Two boomerangs here. And you'll notice that the pink one is larger than the yellow one.
Let's just snap the finger. We're going to cause this yellow one to increase in
size. If I've been successful, check it out. I think that worked. But wait, there's one more
thing that I can do. If i just cause a little bit of a minor spell here. If I snap the finger,
we'll enlarge the pink one just a little bit and you'll now notice that they are the same
size. Here's what you'll need for the trick. You'll need two sheets of paper. It helps
to have different color papers and you can use the same colors for the boomerangs. But you'll
probably want to label them so there's a little bit different about them. For the trick itself,
you'll need a pair of scissors. You'll want some type of pen or something to mark with.
And what are these? What''s the cup and the soup mug for? Well, this is so you can actually create
your own boomerangs. So let me show you how to do that. So let's set this aside for now. Take your
two sheets of paper line and them up. What you're going to do is take your - you have to go through
the house and look for circles with bowls, plates, or cups, whatever you have. I've chosen these two
because what I want are two different diameters. There's a diameter here and a diameter here.
So the one with the larger diameter is going to create the outer diameter. The smaller one will
create the inside diameter. So let me show you how that works. I'm going to take this, place
it down. I'm going to trace along the edge. All I need is a semi-circle. So let's just do that.
And I have a semi-circle. Now with this one, I'm going to use this small diameter here
to make an inner diameter.
Now it's important to try and get this lined up. So this is at the center here
of the outer diameter so i'm just going to estimate and let's draw an inner diameter.
And that's looking pretty good. Perhaps it's not as even as I would like but that's okay
the purpose of the trick - that will work. So we have an outer diameter semi-circle and inner
diameter semicircle. Line the papers up and now you're going to use your scissors to cut
this out. You want the two papers together because you want these to be identical. So let's do that.
Now you have two arcs or rainbows. And the last thing you have to do is,
you're going to want to trim it somewhere about here so you don't have a semi-circle. The trick
works a lot better when you have a shorter arc. So I'm just going to eyeball that in.
I'm going to do something right about there and something right about there.
Now you have your boomerangs. Hee's how to perform the trick. As we showed you in the construction,
the boomerangs are the exact same size. It's just an optical illusion. Turns out that whichever
boomerang is held on top always looks smaller. The illusion is apparently caused by the fact
that you're always measuring the inside diameter of the upper boomerang with the outside diameter
of the bottom one. So no matter which way you hold them, the upper boomerang always looks smaller.
And that's the secret. So all you have to do is just follow the storyline and just
switch the positions and they'll change seemingly change in size for spectators.