Volume of Prisms and Pyramids

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Volume of Cylinders, Cones, and Spheres

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
 Replay
Your next lesson will play in 10 seconds
  • 0:05 Prisms and Pyramids
  • 0:27 Types of Prisms
  • 1:29 Volume of Prisms
  • 3:14 Types of Pyramids
  • 3:50 Volume of Pyramids
  • 5:45 Lesson Summary
Add to Add to Add to

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Login or Sign up

Timeline
Autoplay
Autoplay

Recommended Lessons and Courses for You

Lesson Transcript
Instructor: Jeff Calareso

Jeff teaches high school English, math and other subjects. He has a master's degree in writing and literature.

In this lesson, we'll learn about prisms and pyramids. We'll look at the different types of prisms and pyramids, as well as practice calculating volume for each shape.

Prisms and Pyramids

Prisms and pyramids are everywhere. If you've ever seen the cover of Pink Floyd's Dark Side of the Moon album, then you've seen a prism in action. Pyramids are even more pervasive. If you have a dollar bill in your wallet, then you're walking around with a picture of a pyramid.

Each of these shapes can be found in different forms. Let's take a closer look at what those are and then work on finding the volume of these shapes.

Types of Prisms

Let's start with prisms. You've probably seen all different kinds of prisms. There are the glass ones used for tricks with lights, like turning sunlight into rainbows. Tents can also be prisms. If you're a chocolate lover, then you know that Toblerone packages their chocolate in prism-shaped boxes.

A prism is a three-dimensional shape with flat sides and two parallel faces. What does that mean? Well, those examples above are all triangular prisms. Notice that each face is a triangle. Those are the parallel faces. And the sides? Yep, they're flat. They're also parallelograms. One way of thinking about prisms is that if you make a slice anywhere that's parallel to the face, the shape will always be the same.

Not all prisms are triangular. There are also square prisms. These include cubes where all six sides are the same, but as long as the faces are squares, it's a square prism. See, prisms are defined by those faces. If the face has five sides? It's a pentagonal prism. Also, a barn. That may be a barn.

Volume of Prisms

Let's say you need to find the volume of a prism. For example, maybe you're camping and you want to fill your buddy's tent with marshmallows. You need to plan stuff like this.

Ok, the volume of a prism is pretty straightforward. Start with the area of the face. If it's a triangle, that's 1/2*b*h. If it's a square, it's s^2, and so on. Then you just multiply it by the height of the prism. So the volume of a prism is the area of the base (B) multiplied by the height between the bases (h), which we can just write as B*h.

Now, back to that tent. The front, or face, is a triangle. If the base is 4 feet long and it's 4 feet high, then the area is 1/2*4*4, or 8 square feet. Now, this tent is 7 feet long, so that's the height. The volume is just B*h, or 8*7, which is 56 cubic feet. So you're going to need 56 cubic feet of marshmallows. That's a lot of marshmallows.

Let's look at another example. Let's say you've moved up from camping pranks and you're hosting a wine and cheese party. You may have a block of cheese you're trying to slice into cubes. Each cube is one cubic centimeter. How many cubes can you get from this cheese?

This is a rectangular prism, so you need to know the area of the rectangle and the height. The face of the cheese is 3 cm long by 7 cm wide. The area of a rectangle is length times width. 3*7=21 square centimeters. The height of this block is 14 cm. So the volume is B*h, or 21*14, which is 294 cubic centimeters. So you'll have 294 tiny cubes of cheese. Oh, and if you're like me, remember to subtract a few that you'll eat while you slice.

Types of Pyramids

Next, let's look at pyramids. People often confuse prisms and pyramids. But you'll never see a rainbow if you hang a pyramid in your window. When people think of pyramids, they think of the pyramids in Egypt. Why? Because they're totally awesome!

To unlock this lesson you must be a Study.com Member.
Create your account

Register for a free trial

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use Study.com

Become a Study.com member and start learning now.
Become a Member  Back
What teachers are saying about Study.com
Free 5-day trial

Earning College Credit

Did you know… We have over 160 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? Study.com has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it free for 5 days!
Create an account
Support