Login or Register to add to your saved resources. What is a prism? A prism is a type of three-dimensional 3D shape with flat sides. It has two ends that are the same shape and size and look like a 2D shape. It has the same cross-section all along the shape from end to end; that means if you cut through it you would see the same 2D shape as on either end. NB: A cylinder has two ends with the same shape a circle but because it has curved sides it is not a prism. What is a pyramid?
A pyramid is also a three-dimensional 3D shape. It looks like a hexagon, but because it has some thickness it is actually a hexagonal prism! All the previous examples are Regular Prisms, because the cross section is regular in other words it is a shape with equal edge lengths, and equal angles. Play with it here. Cones, cylinders and spheres aren't prisms because some or all of their sides aren't flat.
There are several types of prisms, such as:. Cubes are often the easiest and most common prism to locate in everyday life.
A cube has equal-length sides and same-size faces, giving it a three-dimensional square shape. Examples of common cubes include: dice, square ice cubes, Rubik's cubes, square tissue boxes, sugar cubes, solid square tables and square pieces of cake, casserole, fudge or cornbread.
Children's toys, such as solid wood, plastic and fabric blocks, are available in cube shapes. Some outdoor planter stands and decorative seating, such as ottomans, come in a variety of cube sizes. Rectangular prisms are similar to cubes, but the cross sections are rectangular with unequal adjacent sides, giving them a 3-D rectangular shape. Some examples in everyday life include: rectangular tissue boxes, juice boxes, laptop computers, school notebooks and binders, standard birthday presents -- such as shirt boxes -- cereal boxes and aquariums.
Larger structures, such as cargo containers, storage sheds, houses and skyscrapers are also rectangular prisms. Even though you don't see too many examples of pentagonal prisms in daily life, one is quite common -- the barn.
The bases on pyramids and prisms differ. Prisms have two congruent -- or identical -- bases, and pyramids only have one base. The shape of the base on pyramids and prisms can vary, depending on the shape of the overall three-dimensional object. For example, the base could have a square, rectangle, triangle, hexagon, pentagon or octagon shape. The base is never a circle or an oval on a prism or a pyramid.
The side-by-side faces, also known as lateral faces, on pyramids and prisms have different attributes. Prisms have rectangular lateral faces and pyramids have triangular lateral faces. In most cases, the lateral faces of both prisms and pyramids are angled toward the base or bases. The rare exception is the "right prism" -- the faces are perfectly perpendicular to the base. The lateral faces are congruent triangles on a "right pyramid.
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