The diameter of a circle is twice the length of its radius. This means that to find the diameter, you can simply multiply the radius by 2. In this case, if the radius is 8 cm, you can calculate the diameter as follows:
- Diameter = 2 × Radius
- Diameter = 2 × 8 cm
- Diameter = 16 cm
Therefore, the diameter of the circle is 16 cm.