Read the text and answer the questions. Give a word or
a phrase as your answer.You may know 3D movies. You may have even seen such a
movie. The ‘D’ in 3D stands for dimensional. A dimension is a direction that
something can be measured.
Flat things can be measured in two ways. They can be
measured by length and by width. That’s why flat things are sometimes called 2D
or two-dimensional.
Three-dimensional objects can be measured in three
ways. They can be measured by length and width like flat things. They can also
be measured by their height. Height is what lets them come up off the paper or
the screen.
Three-dimensional shapes in math are called solids.
Let’s look at some of the most common solids:
A cube has six square sides. The sides are called
faces.
A rectangular prism has six sides that are all shaped
like rectangles.
A square pyramid has a square on the bottom, and four
triangular sides.
A sphere is shaped like Earth. It is also like a
playground ball.What is a dimension?