To find the volume of a cone with the same radius as a sphere and a height equal to the sphere's diameter, we first need to determine the radius of the sphere from its given volume.
The formula for the volume \( V \) of a sphere is:
\[ V = \frac{4}{3} \pi r^3 \]
Given that the volume of the sphere is \( 72 , \text{m}^3 \), we can set up the equation:
\[ \frac{4}{3} \pi r^3 = 72 \]
To solve for \( r^3 \), we will multiply both sides by \( \frac{3}{4\pi} \):
\[ r^3 = \frac{72 \cdot 3}{4\pi} = \frac{216}{4\pi} = \frac{54}{\pi} \]
Now, we need to find \( r \):
\[ r = \left(\frac{54}{\pi}\right)^{1/3} \]
Next, we calculate the diameter of the sphere, which is:
\[ \text{Diameter} = 2r = 2 \left(\frac{54}{\pi}\right)^{1/3} \]
Now that we have established the radius and height of the cone, we can use the formula for the volume \( V \) of a cone:
\[ V = \frac{1}{3} \pi r^2 h \]
Here, \( h = 2r \). Substituting this into the formula gives:
\[ V = \frac{1}{3} \pi r^2 (2r) = \frac{2}{3} \pi r^3 \]
Now, we can substitute \( r^3 \) (which we found earlier):
\[ V = \frac{2}{3} \pi \left(\frac{54}{\pi}\right) \]
This simplifies to:
\[ V = \frac{2 \cdot 54}{3} = \frac{108}{3} = 36 , \text{m}^3 \]
Thus, the volume of the cone is:
\[ \boxed{36 , \text{m}^3} \]