Class 7 - Arjun
Class 7 - Arjun
Ex 12.1
- solid shapes - plane figures
- 2D figures and 3D figures
- Faces - plane surface that encloses a solid
- Edges - 2 faces meet or intersect
- Vertices - 3 edges meet or intersect
- cuboid - 6F - 12E - 8V
- cube - 6F - 12E - 8V
a cube is a cuboid but a cuboid is not a cube
- prism - polygon with lateral surfaces always rectangle
- types of prism based on the base of the prism
- triangular - 5F - 9E - 6V
- pentagonal - 7F - 15E - 10V
- hexagonal - 8F - 18E - 12V
- cuboid - rectangular prism - 6F - 12E - 8V
- cube - square prism - 6F - 12E - 8V
- pyramid - base of polygon and lateral faces are all triangles with common vertex
- types based on the face of pyramid
- triangular pyramid - tertrahedron
- rectangular pyramid
- hexagonal pyramid
- polyhedron - shape with many faces
- " V + F - E = 2" - Euler
- Cylinder -
- base and top - circles
- lateral surface - curves
- no vertex
- line joining the base and top = axis of cylinder
- Cone - pyramid with circular base
- every point of the circumference is joined to a point outside the base - vertex
- plane circular base
- lateral surface is curved
Net of different shapes
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Cuboid ![obsidian|250][NetCuboid.png]
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Cube
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prism triangular prism
hexagonal prism ![obsidian|250][Hexagonal-Prism-Net.jpg]
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pyramid ![obsidian|250][Square-Pyramid-Net.jpg]
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cylinder ![obsidian|250][cylinder-net.png]
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cone
Ex 12.2
- drawing solid shapes
Ex 12.3
- visualising solid shapes
- cutting or slicing
- from different angles or view
- arial or top view
- front view
- side view
- shadowing from different sides
