Surface Area of a Cylinder

The cylinder's surface area can be seen as three separate parts that are top, bottom, and side. The area of the side has the shape of a rectangle of width h. The top and the bottom are circles of radius r.

Since the top and the bottom are congruent circles, they have the same area. cc Area of & Area of One Circle & Two Circles [0.8em] A=π r^2 & A=2π r^2 To find the area of the rectangle, its length must be found first. The length of the rectangle that forms the lateral part of the cylinder is the circumference of the base, which is 2π r.

Therefore, the area of the rectangle is the product of h and 2π r. Area of the Rectangle A=2π rh The surface area of the cylinder S is the sum of the areas of the rectangle and the circles.