You can see a lot of figures here: a cuboid, a cylinder, a pyramid and two cones. They have a length, a width and a height and are therefore three-dimensional (3D). If you hold them in the laser plane and ‘cut through’ them, you can discover many flat figures. You will see a triangle, a square, a circle,… These only have a length and a width and are therefore two-dimensional (2D).
You should also try out the cones. Not only can you make flat figures with them; you can also use them to make special curved lines, or curves, such as the parabola and the hyperbola.
Cross sections in the hospital
Did you break something or are you in a lot of pain? The doctor will try to find out what’s wrong. Sometimes this requires additional exams, such as a CT scan. In a CT scan, they take a lot of images of a part of your body. These images are cross sections: a lot of thin slices. This picture shows the images of someone’s head.
The computer can make a 3D image of these thin slices again so your doctor can learn much more about your bones or tissue.
Cross-section of a tree trunk
The cross-section of a tree trunk shows how many annual rings it has. By counting them, you can find out how old the tree is. Check out our Science Garden.
