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Exploring Geometric Solids. Created by Mandy Plunkett Modified by Charlotte Stripling. Plane Figures. Sphere. A 3D figure shaped like a ball. Formed by … rotating a circle. How can you form a sphere?. Cylinder. A 3D figure that looks like a tube with 2 circular bases. Formed by …
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Exploring Geometric Solids Created by Mandy Plunkett Modified by Charlotte Stripling
Sphere A 3D figure shaped like a ball. Formed by … rotating a circle
Cylinder A 3D figure that looks like a tube with 2 circular bases. Formed by … Rotating a rectangle or square, Translating a circle
Cone A 3D figure with a circular base and a point opposite the base. Formed by … rotating a triangle, stacking similar circles (smaller and smaller until a point)
Cube A rectangular prism with all edges the same length. Formed by … translating a square (its exact side length)
Rectangular Prism Formed by … translating a square or rectangle A 3d figure that looks like a box.
Triangular Prism A prism whose bases are triangles. Formed by … translating a triangle
How can you form a pyramid? • Stack similar figures – smaller and smaller up to a point. • Similar triangles – triangular pyramid • Similar rectangles – rectangular pyramid • Similar squares – square pyramid • Similar pentagons – pentagonal pyramid • Similar hexagons – hexagonal pyramid
Square Pyramid Formed by … stacking similar squares (smaller and smaller until a point)
Triangular Pyramid Formed by … stacking similar triangles (smaller and smaller until a point)
Hexagonal Pyramid Formed by … stacking similar hexagons (smaller and smaller until a point)
DEFINITIONS • Cross Section: the intersection of a plane and a solid. Formed by slicing through a 3D figure and looking at the inside 2D plane figure. • Ellipse: an oval 2D figure. Formed by slicing a 3D figure at an angle to its circular base (oblique).
What cross-sections can I make from a sphere? • Circle (any direction)
What cross-sections can I make from a cube? • Square (vertical or horizontal), triangle (corners), hexagon (oblique), pentagon (oblique), parallelogram (oblique), rectangle (diagonal) To see all cross sections click on link. http://www.learner.org/courses/learningmath/geometry/session9/part_c/index.html http://www.learner.org/courses/learningmath/geometry/session9/part_c/index.html
What cross-sections can I make from a cylinder? • Rectangle (vertical), Circle (horizontal), Ellipse (oblique)
What cross-sections can I make from a cone? • Triangle (vertical), Circle (horizontal), Ellipse (oblique)
What cross-sections can I make from a rectangular prism? • Rectangle (vertical or horizontal), Triangle (corners)
What cross-sections can I make from a square pyramid? • Triangle (vertical), Square (horizontal), Trapezoid (vertical not through vertex)