What is water, everyone knows. This is the same liquid that flows from the tap we drink, which we wash and use for cooking. It is filled with lakes, seas and oceans, it is contained in the soil, underground and in heaven. It spills on the ground in the form of rain in the warm season, and in winter it covers the whole earth in the form of snow and ice. Yes, and man himself is almost eighty percent composed of the same water. Even school goers know that the chemical formula of water reads as H 2 O (“al two o”), and even know that H is hydrogen, and chemists mean oxygen by O.
Without water, no living organism can exist on our planet. Environmentalists scare us that most of the water on the planet is not suitable for drinking, as it contains a large amount of dissolved salts - sea and ocean water. And fresh water reserves are today about 80,000 cubic kilometers. Is it a lot or a little? Let's see how much it will be in cubic meters and in liters, that is, find out how many liters are in 1 cubic meter of water, since, strictly speaking, a cubic kilometer is not a system unit. One cubic kilometer contains a billion cubic meters.
The numbers are impressive, aren't they? There is still a lot of water on our planet. But how much is it in liters more familiar to us? After all, we never measure water by cubic meters, we measure the volume of liquids in liters. So, let's figure out how many liters are in one cube of water. Let's start dancing from the name.
One cubic meter is a cube with sides equal to one meter. Let's build such a cube. If we pour a liter of water into this cube, for example, from an ordinary liter jar or
measuring cup, then it will cover only the bottom of this cube. And the answer to the question: "How many liters are in 1 cube?" - We can only get if we fill this cube to the top.
It is clear that nobody wants to run with a liter jar from the tap to the cube. Therefore, you can use a bucket or just build a smaller cube. We are able to count everything and know for sure that the easiest way is to divide by 10. So let's build a cube with a decimeter side. Our jar filled this cube to the top! Hooray!
Now you can simply calculate how many liters of water in one cube. If one liter is equal to one cubic decimeter, then you just need to calculate how many of these cubic decimeters in a cubic meter. If you take a square, you can calculate quickly - there are exactly 100 of them, that is, 10 in the second degree. But we have not a square, but a cube. Therefore, how many liters are in 1 cube of water? Right, exactly 1000.
Would you have the perseverance to run 1000 times with a liter jar? I doubt it. And mathematics, or rather even arithmetic, helped do just one trip for water. Now we know exactly how many liters are in 1 cube of water. It remains only to convert cubic meters to cubic kilometers, and you can calculate what are the reserves of fresh water on our planet.
Another interesting fact is that one liter of pure water (distilled) under normal conditions weighs exactly one kilogram. So now, knowing how many liters in 1 cube of water, we can calculate the total weight of fresh water on the planet. And if you want to know the total weight of water in all the seas and oceans, then you will have to consider that the density of salt water is higher than fresh, therefore, a liter of salt water should weigh more.