Volume of Prisms

Teachers' Notes

The programme aims to provide real examples of 3-dimensional objects that should help students to visualise the properties of prisms, recognise commonly examined cross-sections and identify the dimensions necessary for volume calculations. It is hoped that the use of clear images and calculations in context will enhance other volume work in the classroom. It is assumed that students will have met the concept of volume prior to viewing and be familiar with the units used. The formula 'Volume = area of cross-section x length' is used throughout and examples emphasise which measurements are needed for a range of different cross-sections, including cylinders. Students should be comfortable with calculating areas, particularly the area of a trapezium and the area of a triangle. Some students may benefit from revision of these prior to viewing. Examples also include composite shapes as cross-sections. Conversion between units is covered but could usefully be developed further through discussion during or after viewing.

The programme would be most suitable for students who have already done some introductory work on volume of prisms. Students may benefit from viewing short sections of the programme as they progress through stages of the work and then view the entire programme to summarise the main points. The programme could also be used as a revision tool or to consolidate understanding at the end of the topic.

Katie gave the following information about the hexagonal fish tank. The tank is 40cm high.

Students should find that the volume is 23 400cm³. The largest tank contains 3.8 million litres of water and Katie invites viewers to consider how many hexagonal tankfuls would be needed to fill the biggest tank.

The answers to Worksheet 1 could be used as the basis for a discussion after viewing. For revision purposes, students may find it useful to have their own copy of the Key Facts and Exam Tips section of these notes. These could be edited and amended to meet individual needs.