Surface area of a cylinder
Cylinder This page explains how to find the surface area of a cylinder. There are some exercises and solutions on this page too. The area equals the added area of the bottom, the top and the sides. The bottom and top size are the same (otherwise it wouldn't be a cylinder). The formula for the cylinder surface area, with radius r and height h: Surface area of a cylinder

Note that the side area is actually a rectangle with the height being the length of the circle circumference, and the width of the rectangle being the height of the cylinder.
Surface area is expressed in square meters (m2) or square feet (ft2). One square meter equals 10,8 square feet.

Exercises
  1. Calculate the area of a cylinder with radius 18 and height 42.
  2. A glass of water is has height 15 and diameter 8. What is the surface area?
  3. Consider a cylinder with surface area 800 and radius 5. How much is the height?
Solutions
  1. 2 * π * 182 + 2 * π * 18 * 42 = 6786
  2. Note that the glass doesn't have a 'roof': π * 42 + 2 * π * 4 * 15 = 427.
  3. The height of the original cylinder: (800 - 2 * π * 52)/(2 * π * 5) = 20,46.

You might want to have a look at our other pages about math, geometry, volumes and shapes!