About this video
The video matches five 3D shapes to their names: square pyramid, rectangular prism, triangular prism, sphere and cylinder. It explains what each name means, such as a square pyramid having a square base and a triangular prism having two opposite triangle faces.
You'll be able to
- name a square pyramid, rectangular prism, triangular prism, sphere and cylinder.
- explain the difference between a square pyramid and a triangular prism.
- describe a cylinder using its two circular faces.
Key words
- square pyramid
- A pyramid whose base is a square, with triangle faces meeting at a point.
- rectangular prism
- A 3D shape whose faces are all rectangles, like a brick or box.
- triangular prism
- A 3D shape with two opposite triangle faces joined by rectangles.
- sphere
- A perfectly round 3D shape, like a globe or ball.
- cylinder
- A 3D shape like a can, with two opposite circles for its ends.
- base
- The face a shape rests on, which often gives the shape its name.
Transcript
- [Narrator] So I have five three dimensional shapes over here, and I also have five names for them. And what I want you to do is pause this video and think about which of these shapes is a square pyramid, which of these is a rectangular prism? Which one is a triangular prism?
Which one is a sphere and which one is a cylinder? All right, now let's just work through this together. And really this is just something to know because some people in various subjects will sometimes throw out these words. So first let's start, let's think about which one is the square pyramid.
So this shape here on the right clearly looks like a pyramid. And the thing that makes it a square pyramid is the idea that its base is a square. Let me see if I can shade this in. So the base of this right over here is a square. So that's where the square pyramid comes from.
If it's a triangular pyramid, then the base would only have three sides, but this is a square pyramid. So let me move this over there. So that is a square pyramid. All right, let's do the next one. Which one is a rectangular prism? A prism you can view as a three dimensional object.
And since it's saying rectangular prism, well the best one here that is rectangular, notice this shape right over here is rectangular on every side. And it's three dimensions. It is a prism. And so this is the rectangular prism. So let's move that over. So that is our rectangular prism.
Now, triangular prism, so this one is interesting. If you look at this shape right over here, it has sides that are triangles. You see this up here is a triangle. And you see this down here is a triangle, although they're connected by these rectangular sides. And this is actually what's called a triangular prism.
In a square pyramid, the faces which are triangles all meet at a point. In a triangular prism, you have two opposite facing sides that are triangles. And you'll see all of these in different orientations, in different, you know, sometimes it'll be resting like this, sometimes it'll be on its side.
But this is a triangular prism. Let me- so that is a triangular prism. And so we have two left. You might be able to figure these out. Which one is a sphere? Well, when I think sphere, I think of like a globe. And so this choice right over here is clearly a sphere.
So let me move that over. Let me move it over. Okay, so that one is a sphere. And then last but not least, a thing that looks like a can is a cylinder. So let me move that over. So that is a cylinder and we're all done. And so these are just useful names to know for shapes.
Cylinder is, you're connecting, you have these two faces that are circular and then they're opposite each other. It's kind of like a triangular prism. But instead of having these hard edges, 'cause you have a triangle, you have a base that is a circle and a top that is a circle.
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