How do you calculate the edge length of a cube?

What you need:

• Basic knowledge of cubes, volumes, roots

Volume of a cube - this is how it is calculated

• The volume of a body is a measure of its volume, for example the amount of liquid that can be filled into this body. The volume is therefore often given in liters (l), but also in cubic meters (m³) or cubic centimeters (cm³).
• A cube is a straight body with the same width, length and height. The typical dice are the simplest example of such a body. For the sake of simplicity, the width, length and height are called the edge length of this cube.
• The volume of a cube naturally only depends on how large this edge length is. The simple relationship volume = edge length to the power of 3 applies. So you have to multiply the edge length by yourself three times.
• If you denote the edge length with the letter a and the volume with V, you get the formula V = a³. With an edge length of a = 2 cm, the cube accordingly has the volume V = (2 cm) ³ = 2 cm x 2 cm x 2 cm = 8 cm³ (i.e. 8 cubic centimeters).
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Edge length of a cube - the reverse task

If you now have the volume of a cube for a task and the edge length is to be calculated, it is, so to speak, the inverse task. To show the procedure, let us assume a cube with a volume of V = 240 cm³ and calculate its edge length a:

1. Plug the given volume into the formula and you get 240 cm³ = a³. The unknown is to be calculated a.
2. Mathematically, you have to do the opposite operation to the third power here. This is (analogous to the square and the root, by the way) to pulling the third root, also called the cube root. So you're looking for a number that, taken three times by itself, is 240.
3. Of course, you can rarely do this in your head. So you need a book of tables, the third root or contains cube roots or one calculatorwho will charge you for this.
4. Some calculators have their own key for calculating the cube root, otherwise use the x key^y respectively ^y√x for this task. For x, insert the given volume V (here 240), in the first case y = 0.333 (for 1/3), in the second case y = 3 (for the third root). For the edge length you get a = 6.21 cm (rounded to two places behind the decimal point).
5. There are so-called on the Internet Root calculatorthat you can use to grow any roots. Enter "3. Root (cube root) "as well as the Counting "240" and you get the result to 11 places behind the decimal point. Rounding is of course also required here.