# Understanding volumeÂ (liters)

CCSS Math: 3.MD.A.2

## Video transcript

- [Voiceover] What I want
to talk about in this video is the liter. The liter. Let me write this down. The liter and the liter is a unit for measuring fluid volumes, or how much space does a fluid take up. So what does one liter look like? Well one of these milk bottles is a liter and your most typically going to think about a
liter in your everyday life when your buying some type
of beverages, milk, or water. In fact next time you
go to the grocery store see a lot of the bottles you get. They might be exactly one
liter, some of the soda bottles are two liters, but this
right over here is one. One liter, we write a capital
L for short, that's one liter and so there's six liters in total in this little carrying case but each of these milk
bottles is one liter. So that's a liter but
what if we want to go to really small volumes of water? Well if we want to go to
really small volumes of water we normally talk about milliliters. Milliliters, let me write this down. Milli Milli Milliliters. Actually
let me write it this way. Let me write milli in another color. Milli Milliliters. So it's a milli liter. And a milliliter, a milli is a prefix that you'll see a lot
when your using units and that means one
one-thousandth of a liter. So this means one one-thousandth. One one-thousandth of Of a of a liter and the notation for milliliter is a lowercase m and and uppercase L. Milli liter. Another way to think
about it, it would take one thousand milliliters
to get to one liter. So what does a milliliter look like? Well if you imagine
these medicine droppers, a milliliter would be about that high on one of those medicine droppers and a lot of these medicine droppers actually will have a milliliter, actually they'll have
up to five milliliters marked off but a milliliter
will be about that much or if you were to take a teaspoon from your cabinet in your kitchen and you would scoop out
a teaspoon of water, that, so this one over here
is going to be one milliliter and a teaspoon of fluid,
that's going to be about five. That's going to be about five milliliters. So another way to think about it is you would have to take a
thousand of these drops to fill one of these bottles of milk. A thousand milliliters to get to one liter or you would have to do, let's see, five, you'd have to put five, sorry, you'd have to do
two hundred teaspoons of say milk, to fill up this entire thing because each of them is five milliliters. Two hundred times five milliliters, you're going to have
a thousand milliliters which is one liter. Let me write this down. This right over here, this is one liter which is the same thing as one thousand, one thousand milliliters. Now what if we go to things that are much larger. What if we go to things
that are much larger than the scale of a jar of milk. Say a swimming pool and
this right over here, this is a picture of a
olympic size swimming pool which is, for the most
part, the largest pools, well there some larger pools
in some fancy hotel and things, but they're very large pools. So what do you think would be if one milk bottle has a, one like this, has a fluid volume of one liter, what do you think about
a whole swimming pool? Well actually a swimming like this, if it is 25 meters wide and 50 meters long and two meters deep,
it actually would have a fluid volume, are you ready for this? It would have a fluid volume
of 2.5 million liters. So if you filled this up with
milk, you can use that milk to fill up 2.5 million of these bottles. So that's just an appreciation
for just how much fluid it would take to fill up at least a big swimming pool like this, an olympic size swimming pool. A swimming pool that you
might more typically see at someone's house, who isn't, you know, that doesn't have an
olympic size swimming pool so kinda of a house size swimming pool, it's still going to be,
it's not usually to see one that will be more than one hundred, 100,000 100,000 liters. So once again, are you
thinking about teaspoons or drops from a dropper, your thinking in the milliliter range. If you're thinking about the type of, something that you might drink in a day or that your family might
drink over, say a week, you're thinking in,
really, the liter range. And if you're thinking about
how much fluid it would take to fill a swimming
pool, now you're talking in the tens of thousands
or hundreds of thousands or even millions of liter range.