1. Volume of Prisms @dwatson802 2004

2. 1-D, 2-D and 3-D shapes A straight line is one dimensional (1-D). It has only length. Units mm, cm, m & km etc. A rectangle and a circle are two dimensional (2-D) shapes. They have area. Units mm 2, cm 2, m 2 etc. A cube and a football are three dimensional (3-D) objects, They have volume (or capacity). Units mm 3, cm 3, m 3, litres etc. length

3. The Volume of a Prism A prism is a 3-D shape which has the same cross-section throughout its height.The following shapes are all prisms: Cuboid Triangular prism Pentagonal prism Volume of a prism = area of cross-section x vertical height

4. Formulae for Spheres and Cylinders r Surface Area = 4πr 2 4πr 3 3 Volume of A sphere = A cylinder is also a prism Therefore = area of cross-section x vertical height

5. Example Volume of a prism = area of cross-section x depth 18cm 2 10cm

6. CUBOID example 5cm 8cm 20cm

7. Example 6cm 5cm 10cm Find the Volume of this triangular prism.

8. Example 6cm 5cm 10cm Area of cross section = ½ x base x height = ½ x 5 x 6 = ½ x 30 = 15cm 2 Volume of a prism = Area of cross sectionx depth Volume of a prism = 15 x 10 = 150cm 3 Find the Volume of this triangular prism.

9. Area = 20m 2 8m A = 36m 2 5m A = 14m 2 10m A = 12m 2 15m 12m 8m 2m 4m 10m 3m A = 15m 2 11m 5m 4m 10m 3m 6m 10m 1) 2) 3) 4) 5) 6) 7) 8) 9)

10. Plenary! 20cm 3cm 2cm 7cm

11. 3cm 2cm 7cm

12. 3cm 2cm 7cm 20cm