Prisms and Cylinders
Prisms
- A prism consists of a polygon on the bottom and a congruent polygon on the top, with all corresponding parts connected.
- Examples:
- Triangular prism: Triangle on the top, triangle on the bottom, with corresponding points connected.
- Rectangular prism (box): Rectangle on the bottom, congruent rectangle on the top, with corresponding vertices connected.
- The bottom and top are always congruent.
Right Prisms vs. Oblique Prisms
- Right prisms: Have right angles.
- Examples: Right triangular prism, right rectangular prism.
- Oblique prisms: The top polygon is shifted or slanted relative to the bottom polygon.
- Example: A square base with the top square moved over.
- Oblique: A fancy word for slanted.
Volume of Prisms
- The volume represents how much water (in cubic inches or cubic centimeters) it would take to fill the prism.
- To find the volume: Find the area of the base and multiply by the height.
- Volume=Area of Base∗Height
- Units of measure: Cubic inches (a cube that is one inch wide, one inch long, and one inch high).
- Height: The distance perpendicular to the base.
- For oblique prisms, the height is not the slanted distance but the perpendicular distance to the base.
Cylinders
- A cylinder is similar to a prism, but the base and top are circles.
- The volume of a cylinder is found by taking the area of the base (circle) and multiplying by the height.
- Volume=Area of Base∗Height
- Right Cylinder: The height goes straight up perpendicular to the base.
- Oblique Cylinder: Similar to an oblique prism.
Summary
- Prisms and cylinders have easily calculated volumes.
- To find the volume: Determine the area of the base, then multiply by the height, regardless of whether it's a prism or cylinder, right or oblique.