To calculate the density of the cube, you can use the formula:
\[ \text{Density} = \frac{\text{Mass}}{\text{Volume}} \]
First, we need to calculate the volume of the cube. The volume \(V\) of a cube with side length \(s\) is given by:
\[ V = s^3 \]
For a cube with a side length of 2 meters:
\[ V = 2^3 = 8 \text{ m}^3 \]
Now that we have the volume, we can plug in the mass and volume into the density formula. The mass of the cube is 40 kg.
\[ \text{Density} = \frac{40 \text{ kg}}{8 \text{ m}^3} = 5 \text{ kg/m}^3 \]
Therefore, the density of the cube is 5 kg/m³.