visualising-solid-shapes-ppt.pdf

Very good ppt of visualising shapes class 8

2. VISUALISING SOLID
SHAPES

3. WHAT ARE SHAPES
Ashapeis the form of an object or its external
boundary, outline, or externalsurface, as opposed to
other properties such as color, texture, or material
composition.
Psychologists have theorized that humans mentally
break down images into simple geometric shapes
calledgeons.
[1]
Examples of geons include cones and
spheres.

4. Contents
1. 2D shapes
2. 3D shapes
3. Regular shapes
4. Irregular shapes
5. Map

5. 2d SHAPES
2D shapescan be summarized by
calling them flatshapes.
Anyshapethat can be laid flat on a
piece of paper or any mathematical
plane is a2D shape. As a child, your
first drawings probably used
basicshapes, such as squares,
triangles, and circles.

6. Examples of 2d shapes
POLYGON
QUADRILATERALS
CIRCLE
TRIANGLE
SQUARE
RECTANGLE
PENTAGON
HEXAGON
OCTAGON

7. MATCH THE FOLLOWING
1.QUADRILATERALS
2.CIRCLE
3.TRIANGLE
4.SQUARE
5.RECTANGLE
6.PENTAGON
7.HEXAGON
8.OCTAGON

8. These shapes are solid or
hollow.
• They have three
dimensions –length,
width and height.

9. Examples of 2d shapes
Cube
Cuboid
Sphere
Cone
Cylinder
Square Base Pyramid

10. Match the following
Cube
Cuboid
Sphere
Cone
Cylinder
Square Base Pyramid

11. Irregular shapes are two dimension structure which
lies in a plane. These shapes will not have all sides
equal and all angles equal. Irregular shape is denoted
as when all the sides of the shapes having different
length and thevalue of angles should not be same for
all the angles.For better understanding we should
know the difference between regular and irregular
shapes. Regular shapes have equal angles and equal
sides for example regular hexagonal, regular pentagon
etc.

12. Examples

13. Regular shapes have equalanglesand
equalsides. Forexample
regularhexagonal, regular pentagon etc.
Below are some examples of regular and
irregular shapes: Regular Shapes: Above
shapes,triangle,square, pentagon
andhexagon, having samesidesand
sameangles.

14. Examples
Square
Regular hexagon
Regular pentagon
Regular octagon
Equilateral triangle
Rhombus

15. Match The Following
Square
Regular hexagon
Regular pentagon
Regular octagon
Equilateral triangle

16. A map is a visual representation of an entire area or a
part of an area, typically represented on a flat surface.
The work of a map is to illustrate specific and detailed
features of a particular area, most frequently used to
illustrate geography. There are many kinds of maps;
static, two-dimensional, three-dimensional, dynamic
and even interactive. Maps attempt to represent
various things, like political boundaries, physical
features, roads, topography, population, climates,
natural resources and economic activities.

17. Map Images

18. Worksheet
Fill in the blanks:
1. A pentagonal prism has ______ faces, ______ edges and
_____ vertices.
2. Give two basic differences between a prism and a pyramid.
3. How many edges are there in a cuboid?
4. What are regular polyhedrons?
5. Give two basic differences between a prism and a pyramid.
State true or false
1. In a map, places that are far & those that are near, will be of the
same size to an observer.
2. If we add the dimension ‘height’ to a rectangle(with certain
length & breadth),we obtain a cuboid.

19. Answers
1. Faces: 7, Edges: 15, Vertices: 10
2. A Prism is a polyhedron in which the base & top are regular
polygons; whereas a pyramid is a polyhedron in which the base is a
polygon. b. In a prism the lateral surfaces are parallelograms;
whereas in a pyramid, the lateral surfaces are triangles.
3. 12
4. A polyhedron is said to be regular if its faces are made up of
regular polygons and the same number of faces meet a vertex.
5. A Prism is a polyhedron in which the base and top are
congruent polygons; whereas a pyramid is a polyhedron in which
the base is a polygon. b. In a prism the lateral faces are
parallelograms; whereas in a pyramid, the lateral surfaces are
triangles with a common vertex.
True--False
1. True
2. True