Question

If the volume in $m^2$ and the surface area in $m^2$ of a sphere are numerically equal then the radius of the sphere in m is

• A. 4
• B. 2
• C. 3.5
• D. 3

Answer 1

The correct option is D 3

Let the radius of the sphere is m

So volume of sphere=$\frac{4}{3}\pi m^3$

And surface area of sphere= $4\pi m^2$

As per question both are numerically equal

$\therefore \frac{4}{3}\pi m^3=\pi m^2\Rightarrow m=3$