The Can That Fooled Engineers

The optimal shape for a can — minimizing surface area for a given volume — is a cylinder where the height equals the diameter (h = 2r). This uses the least tin per ounce of food. But real cans are rarely this shape. Why?

Practical constraints override pure math: cans must stack, fit in cupboards, and be easy to hold. A tuna can is wider than it is tall for shelf display. A Pringles tube is taller than wide so the chips stack without breaking. The mathematical optimum is the starting point, not the final answer — engineering adds human constraints.