Why is a Prism like a Cylinder?

Try increasing the number of sides:


Yes! The prism starts to look like a cylinder!

Also try moving points A and B.


The volume formulas are the same:

V = (Base Area) × Height

For a circular cylinder the base area is πr2 (where r is radius) so we get:

Volume of Circular Cylinder = (πr2) × Height

For a square prism the base area is s2 (where s is side length) so we get:

Volume of Square Prism = (s2) × Height

For other prisms we just have to work out the base area.

Right vs Oblique

And it doesn't matter if it is right (ends perfectly aligned) or oblique (slanted), the volume formula still works, but remember:

The height is at right angles to the base!

oblique cone