Hello guys!
As we mentioned earlier, geometry is everywhere: in buildings, in toys, in the objects that we use every day... Among all the forms that exist, there are two groups that draw attention because of how interesting they are: polyhedra and round bodies. In this blog post we will know how they are, what they differ and why they are more present in our lives than we imagine.
What is a polyhedron?
A polyhedron is a three-dimensional figure bounded by flat polygons called faces, which are joined at edges and vertices. These shapes have defined structures and are studied for their geometric properties.
Elements of a polyhedron:
- Faces: flat surfaces enclosing the volume.
- Edges: segments where two faces meet.
- Vertices: points where three or more faces meet.
Relationships between elements:
They follow the Euler formula:
V- A + C = 2
(where V = vertices, A = edges, C = faces).
Conditions for existence of a polyhedron:
- At least three faces must coincide in a vertex.
- The sum of the angles around each vertex must be less than 360°.
Types of polyhedrons:
- Regular: All their faces are equal regular polygons, and all their vertices have the same number of faces.
- Irregular: Faces with different sizes and shapes.
- Concave and Convex: Depending on whether they sink inward (concave) or protrude outward (convex).
- Deltahedra: Polyhedra with all their triangular faces.
What are Round Bodies?
Round bodies have curved surfaces. They are not formed by flat faces, but by surfaces that result from the rotation of flat figures.
Main types:
- Cylinder: It has two circular bases and a curved surface. It can be straight or oblique.
- Cone: It has a circular base and a vertex. It can also be straight or oblique.
- Sphere: All points on its surface are at the same distance from the center.
You want to learn more? Here are some fun resources:
- Here you have an activity designed by me, in which you must complete with the faces, edges and vertices of each figure.
2. Here I leave you some printable templates, you can cut and paste, so you will see much more visually the faces, edges and vertices of each figure.
3. Finally, visual resources are a great help in teaching. That’s why I leave you a video that explains in an easy and simple way everything we have seen today.
I hope you have learnt!
See you in the next geometric adventure!🧩
References:
Colegio Provincial San José de Pamplona. (s.f.) Solidos geométricos y cuerpos redondos. https://www.webcolegios.com/file/ac4fd2.pdf
Comentarios
Publicar un comentario