ShmoopTube

Where Monty Python meets your 10th grade teacher.

Search Thousands of Shmoop Videos


Math III Videos 103 videos

Unit Rate
20718 Views

Approximately 874 people per day wonder what a unit rate is. If you're one of them, check out our video on unit rates and how to use them. (We just...

Solving Proportions Using Cross Products
6802 Views

This video covers how to use cross products to solve for a missing number in a proportion by setting that proportion with a variable over the produ...

GED Math 2.4 Rational Numbers
190 Views

GED Math 2.4 Rational Numbers. Lucius's favorite restaurant is how many km from his home?

See All

Introduction to 3D Geometry 55502 Views


Share It!


Description:

It's one thing when all those shapes are sitting flat on the page. But when they start popping out and invading our personal space bubble, we get a little nervous. Back off, cylinder.

Language:
English Language
Subjects:

Transcript

00:00

3D Geometry, a la Shmoop. Take a seat. Revenge of the Triangles... in

00:09

3D... is about to begin.

00:11

Pending a few previews. You saw it in lame-o-vision last week...

00:15

...but now it's going to be in all three dimensions, comin' at ya.

00:19

Suddenly, there they are - those terrifying triangles.

00:22

Only, they're not triangles anymore... They're prisms! Horrible, gory, flesh-eating

00:27

prisms. Ever seen light refracted through those glass

00:30

shapes to make a rainbow?

00:32

3D shapes have more than just length and width.

00:34

They have depth, too. Most 3D shapes you can make by gluing a bunch

00:39

of 2D shapes together. Be careful with the krazy-glue, though...

00:42

...you don't wanna walk around with a cylinder glued to your head.

00:45

A flat surface of a shape is called a face... ...the line that connects two faces is called

00:54

an edge... ...and a point on a 3D shape is called a vertex.

01:03

Prisms are two parallel polygons called bases with a bunch of lateral faces that connect

01:08

them. They're named after the shape of their bases,

01:11

so we could have... ...triangular prisms or...

01:15

...hexagonal prisms. Cylinders are like prisms, only the bases

01:19

are circles instead. Pyramids are like prisms, but with only one

01:26

base. And cones are pyramids with circular bases.

01:31

Spheres are like balls... but don't try playing basketball with one.

01:37

They're not regulation. Those are the basic three-dimensional shapes,

01:40

and the ones you'll probably see often. There are other ones like polyhedrons, but

01:45

we won't blow your mind any more for the time being.

01:48

Now that you've got a grip on basic 3D geometry... ...you can sit back, relax, and enjoy Revenge

01:54

of the Triangles... in 3D...

01:57

...or... try to.

Related Videos

Compound Interest
45296 Views

Who wants to be a millionaire? In this video, learn about compound interest, interest rates, and the compound interest formula. You'll be buying th...

ACT Math 5.2 Pre-Algebra
1938 Views

ACT Math: Pre-Algebra Drill 5, Problem 2. If a and b are prime numbers, how many factors does ab have?

Simplifying Radicals
9739 Views

We don't like knocking people down to size, but we do like simplifying radicals. Join us?

Arithmetic Math
2250 Views

If fleeing criminals always fled the scene of the crime at perfect right angles, it would be much easier to determine their whereabouts. Fortunatel...