If the volume of a cylinder is fixed, derive the radius and height that will maximize the surface area

1.5k Views Asked by At

I know how to find the radius and height for minimum surface area. [https://www.physicsforums.com/threads/maximum-surface-area-of-cylinder.332279/ ]. For it to be minimum, h=r/2. It would be great if someone could tell me how to find the values for maximum value.

1

There are 1 best solutions below

0
On BEST ANSWER

There is no maximal surface area.

To see that, start with an arbitary cylinder with the given volume.

Then, divide the height by $4$ and double the radius. The volume does not change, but the area of the circle is $4$ times larger.

You can repeat this process as often as you want. It is clear that there is no upper bound for the surface area.