Which of these shapes is 3D?
In this question, we’re shown
pictures of two shapes. And they look very similar at first
glance. But if we look more carefully, we
can see that they’re actually different shapes. Our first shape is a pyramid. It has a flat base and several
surfaces that go up to a point. It’s just like the pyramids that
were built in ancient Egypt. And our second shape, we know, is a
triangle. Our question asks us, which out of
our two shapes, the pyramid or the triangle, is 3D? 3D is a short way of saying the
words “three dimensional.” A shape with three dimensions has
got length, width, but it’s also got height. A 3D shape is a solid shape, not a
flat shape. It’s more of an object.
So out of our pyramid and triangle,
which one is a solid shape, not a flat shape? We can see that the pyramid is a
solid shape. A triangle is a flat shape. When we think of those huge
pyramids in ancient Egypt, these are big objects. They’re not flat on the ground,
they’re very, very tall. A pyramid is a 3D shape.