Hi, I'm Jared, welcome to our channel of fun science demonstrations.
What am I holding in my hands? Well, you should recognize this as a thermometer.
What's the purpose of a thermometer? Well, it measures
temperature. Temperature is how much heat energy
an object has. And that object could be anything. It could be the air,
it could be this water, it could be this ice, it could be me.
All of those things have heat energy and I can measure it
with a thermometer. And wouldn't you know, we're going to be making our own
thermometer
today. So when I pull this thermometer out-this just a little plastic thing that has
marks so I can tell
how much heat energy something has-it's basically made up of a tiny container
that has red liquid in it. Well, guess what? We're going to make our own little
tiny container
with red liquid in it and see if we can measure heat energy.
So, what do I need to make my thermometer? Well, I need a bottle with a lid,
some red food coloring if you like, a pushpin
to start a hole, a pencil to make that hole bigger and then a straw, some kind
of straw,
to go through the hole in the bottle. Let's see this thing work.
So, I'm actually going to keep the lid on my bottle, I'm going to take my pushpin and go
right through the center of the lid.
Wiggle it around a little bit and I have a tiny, tiny hole. Now,
keeping the cap on the bottle so I don't, so I don't get myself with the tip of
the pencil,
I can use my pencil. I'm going to twist and push
at the same time. It's a real simple way to make a small hole
into a big hole. Now, take the lid off, and I'm going to take my straw
and I'm going to pull it through the hole
and make sure my straw doesn't touch the bottom.
Make sure my straw doesn't touch the bottom of my bottle.
Now, I just have to fill my thermometer up
so we can start measuring heat energy. So, now let's fill
the thermometer. I'm going to take the cap off,
and I'm just going to fill this most of the way with water.
I can fill it to the top, I don't have to. I can leave a little bit of air space.
Now, so that you can see it better and so that it looks more like a thermometer,
I'm going to add some red food coloring. A couple of drops, a lot of drops,
you can make it any shade of color you'd like. Now,
I need to put the cap back on,
and I have a problem. I have to increase the water level
in my straw. I could do this a couple of different ways. I could have a food
dropper or
an eyedropper and add water to the straw, or I could use a
a different technique, and I like this technique. All I'm going to do is blow into the
straw, just really gently, you'll see air bubbles come up
and it'll raise the water level in the straw. Check this out. And what do you
know!
So, I made up my own little thermometer out of a glass jar. That way
squeezing it doesn't really affect it. Let's see what happens when I put my
thermometer
in hot water. Watch the water level.
0h, wow, it's rising
just like a real thermometer! My thermometer's measuring the heat energy
of this water.
It must be pretty warm. How do I know that? It's going up.
As things get hot, they actually expand.
Water expands when it gets hot. How do I know that? Well, its expanding!
I wonder what happens if I measure something that doesn't have as much heat
energy,
like this tub of ice. What do you think's going to happen?
Let's find out.
Try to just fit it so it
sits down. And let's watch
the see if we can measure the heat energy in this ice.
I'm just piling some ice up around it.
Now, you can see that my thermometer's moving much slower on its way down than
it did up.
Most thermometers work the same way. I have a little container of red liquid and
when that liquid measures heat energy, if
it has a lot of heat energy, that red liquid is going to move up.
If it doesn't have as much heat energy, that red liquid's going to move down.
A working thermometer. If you want to learn more about heat energy, check out
our links in the video description.
Science is so cool, or hot! Thanks for watching.