Predicting results is an important part of this activity.

The angle that the cut is made on will affect the shape of the section. For example, a cut that is at right angles to the axis will give a circle as the cross section of a cone and a cylinder.

These right-angled cuts are much easier to predict than those that are slanted. When a slanted cut is used, the section is very much influenced by how and where the cut is made. A cut through a circle-based cone at a slant will give an ellipse as a section.

A parabola is formed by cutting through a circle-based cone parallel to a sloping side.

Examples of a parabola shape are:

• the path followed by a ball in flight
  
• the shape of wires supporting a suspension bridge.
  

Answers to Activity

1-3.  Practical activities

4. The sections should look like this:

5. Practical activity