Can science look like magic? You bet!
You're about to learn a series of magic tricks that are based on scientific principles.
You can perform these as magic tricks or you can use them to demonstrate
a scientific principle. Let's get started.
This is one of the best science magic tricks that you can perform
because it actually looks just like a real magic trick.
Just as I showed you in the demonstration, you just place the card on top of the glass and turn
it over. Now hold the card tightly against the glass. Turn it over. And you can release your
hand and the card won't fall and the water won't pour out until you pull the card away.
Here's how it works. First of all, there's surface tension of the water that causes a
seal to occur between the card and the glass. But what really makes the magic happen is air
pressure which is all around us. 14.7 pounds per square inch or psi is pushing all around us
and while it seems counterintuitive it doesn't seem like it could possibly work,
the air pressure outside is greater than the water pressure inside. And thus,
when you release your hand away, the card stays and the water doesn't pour out. And again,
this is one of the best magic tricks you can perform that's based strictly on science.
Check it out. Inside of this bottle where I can't touch it is my magic diver. Here, let's see if
i can command it to do something. We're just going to wave the hand and command it to go down
and I think that's happening right there. And now, back up back up again.
And up again. Take a packet.
Place a paper clip on there for weight. And now place it inside of your empty water bottle.
Now you fill your bottle with water. First of all, you may have to balance the packet that's inside
of the water here. It turns out. I had to use two paper clips so it was just at that right point. So
if the packet sinks to the bottom, you have too big of a paper clip on it (it's too heavy). if it
stays at the top and you can squeeze it with the water all the way to the top, when you squeeze
it just goes right down and when you release it goes right back up.
To perform this trick all you do is squeeze the bottle. It will cause the little diver inside
to move down to the bottom. And when you release the bottle, it'll cause the little diver inside to
come back up. So how does this work? Well, there's water pressure inside of this bottle and when you
compress the water you actually compress some of the air that's inside of that tiny little packet.
Thus, the packet becomes more dense than the water beside it and it begins to drop to the bottom as
you squeeze and increase the water pressure. Gradually release the pressure on the bottle
and the diver or packet becomes less dense and then rises to the top.
I have strips of paper here. Let's see if we can do a little magic. Let's see if you can predict
what's going to happen. First strip here. I'm going to cut all the way along the strip here.
And you get two rings.
Loop number two.
Same cut.
And
I get one big ring.
Loop number three. Can you guess what's going to happen? Same cut
and we get two interlinked rings.
In this trick there are three variations on the loops that you create all I've done here
is taking taken an eight and a half by eleven sheet of paper, cut one and a half inch strips
lengthwise and glued them together right here. And then, at some point, I'm going to
glue them together to make the loops. Now the first one
where we made two loops, identical loops, all I did was glue these together just like this.
And this was cut and created the two loops. In the second one you do what's called a half twist.
So you take this and you twist it halfway like that. And then glue these together.
This is the one that creates the loop of interest. The very long loop. And I will talk a little bit
about the properties of that which is significant to this to the scientific, the scientific angle
to this magic trick. And finally, for the last one where you have two interlinked loops
you twist it a full twist so that would be a half twist and then a full twist. And then
glue these ends together. And then, when you cut lengthwise around this loop, you will get
two interlinked loops. The key to this trick is that you twist these strips in different ways
before having a spectator or yourself cut them. The first one is just a very simple loop of paper
and that's why when you cut it through the center, it creates two loops of the same size
and shape. With the second loop you create a half twist before gluing the ends together.
So what happens here is when you cut through the center you create one giant
loop. Now this loop is has special properties which I'll talk about at the end of this segment.
For the third loop, you actually create a full twist before gluing the ends together.
So when you cut through the middle you create two rings that are locked together.
This trick is based on something called a mobius strip named after August Ferdinand Mobius.
The second loop is of interest because if you trace it all the way around, you'll
notice that you'll go inside of the loop and then outside of the loop. This is very practical for
applications such as conveyor belts because they will not tend to wear on just one side.
They will wear on both sides. Now this trick is a classic that's mentioned in a lot of
magic books and apparently has been used by magicians in their acts. Frankly,
I'm not really sure what the magic is here. It just seems like it's a scientific demonstration
of geometry and topology. But it's kind of fun and something you can do and perform for your friends.