3D shapes - Surface area
Hi Everyone, welcome back to our Maths classes with a new topic 3D Surface Area , another topic in our revision booklet, so let’s get started
Once upon a time, there was a curious young student named Alex who was learning about geometry in school. One day, the teacher introduced the concept of surface area and Alex was immediately intrigued.
"Imagine an object in three-dimensional space," the teacher began. "The surface area is the total area of all its exposed outer surfaces. In other words, it's the sum of all the two-dimensional areas of the object's faces."
Alex thought about this for a moment and then asked, "Can you give me an example?"
"Sure," the teacher said. "Think about a cube. It has six faces, each with a certain area. To find the surface area of the cube, we would add up the areas of all six faces."
Alex was starting to understand. "So the surface area tells us how much 'skin' an object has," he said.
"Exactly," the teacher said. "And it's not just useful in geometry. Surface area is also important in physics and engineering, where it can be used to describe the properties of an object."
Alex nodded, eager to learn more. From that day on, he paid extra attention in class and soon became an expert in surface area.
Let’s focus first on the surface area of a Cuboid
We know the "surface area is the total area of all the exposed outer surfaces of an object. It is like the skin that covers and protects the object.“
"The formula to find the surface area of a cuboid is: Surface area = 2(lw + wh + lh)," the teacher explained. "Where l is the length, w is the width, and h is the height of the cuboid."
Now Let’s focus on the surface area of a Pyramids
Pyramids in mathematics are three-dimensional shapes with a polygonal base and triangular faces that meet at a common point, known as the apex or vertex. Pyramids are a type of polyhedron, which is a solid with flat faces.