VISUALIZING SOLID SHAPES- ESSENTIAL POINTS
- The circle, the square, the rectangle, the quadrilateral and the triangle are examples of plane figures.
- The cube, the cuboid, the sphere, the cylinder, the cone and the pyramid are examples of solid shapes.
- Plane figures are of two-dimensions (2-D) and the solid shapes are of three-dimensions (3- D).
- Vertices are the corners of solid shapes.
- Edges are the line segments of its skeleton
- Faces are its flat surfaces.
- A net is a skeleton-outline of a solid that can be folded to make it. The same solid can have several types of nets.
- 2-D representation of 3-D objects is used to draw solid objects on flat surface.
- Two types of sketches of a solid are possible:
- An oblique sketch does not have proportional lengths. Still it conveys all important aspects of the appearance of the solid.
- An isometric sketch is drawn on an isometric dot paper and measurements of solid are kept proportional.
- Visualizing solid shapes is a very useful skill. You should be able to see ‘hidden’ parts of the solid shape.
- Different sections of a solid can be viewed in many ways:
- View by cutting or slicing the shape and observing the cross section of object.
- Observing a 2-D reflection of a 3-D shape.
- Observing from different angles; the front-view, the side-view and the top view can provide a lot of information about the shape observed.
- A line is straight and extends in both directions forever.
- A plane is a flat surface that extends in all directions.
- A line segment is the part of line between two points.
- A ray starts from a fixed point and goes to any distance to the other direction of the starting point.
