How to Calculate the Surface Area of Cylinders, Cones, and Spheres

Sheena Doria

This instructional video provides a comprehensive tutorial on calculating the surface area of three specific three-dimensional geometric figures: cylinders, cones, and spheres. The video uses a step-by-step approach, starting with the conceptual understanding of how these 3D shapes "unfold" into 2D nets to derive their respective formulas. This pedagogical choice helps students understand the logic behind the math rather than simply memorizing equations. The content covers key geometry themes including identifying lateral faces and bases, understanding the relationship between the circumference of a base and the length of a lateral face, and performing calculations using Pi (approximated as 3.14). It breaks down complex shapes into simpler components—rectangles, circles, and sectors—and demonstrates how to sum these areas to find the total surface area. This resource is highly valuable for middle and high school geometry classrooms. It serves as both a conceptual introduction and a procedural guide. Teachers can use the video's clear animations to visualize the abstraction of nets, and the worked-out examples provide excellent opportunities for guided practice where students can pause, calculate, and check their work against the video's solutions.