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Volume of Prisms. @dwatson802. 2004. 1-D, 2-D and 3-D shapes. A rectangle and a circle are two dimensional (2-D) shapes. They have area . Units mm 2 , cm 2 , m 2 etc. A straight line is one dimensional (1-D). It has only length. Units mm, cm, m & km etc. length.
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Volume of Prisms @dwatson802 2004
1-D, 2-D and 3-D shapes A rectangle and a circle are two dimensional (2-D) shapes. They have area. Units mm2, cm2, m2 etc. A straight line is one dimensional (1-D). It has only length. Units mm, cm, m & km etc. length A cube and a football are three dimensional (3-D) objects, They have volume (or capacity). Units mm3, cm3, m3, litres etc.
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 Pentagonal prism Triangular prism • Volume of a prism • = area of cross-section x vertical height
4πr3 3 r Volume of A sphere = = 4πr2 Surface Area Formulae for Spheres and Cylinders A cylinder is also a prism Therefore = area of cross-section x vertical height
Example Volume of a prism = area of cross-section x depth 10cm 18cm2
CUBOID example 20cm 5cm 8cm
Example Find the Volume of this triangular prism. 10cm 6cm 5cm
Example Find the Volume of this triangular prism. Area of cross section = ½ x base x height = ½ x 5 x 6 = ½ x 30 = 15cm2 10cm 6cm = Volume of a prism Area of cross section x depth 5cm = 15 x 10 Volume of a prism = 150cm3
11m A = 15m2 1) 3) 2) A = 14m2 Area = 20m2 A = 36m2 10m 8m 5m 4) 6) 5) 2m 8m 15m A = 12m2 12m 7) 9) 3m 8) 10m 6m 4m 10m 10m 5m 4m 3m
Plenary! 2cm 7cm 3cm 2cm 20cm 7cm
2cm 7cm 3cm 2cm 7cm
2cm 7cm 3cm 2cm 20cm 7cm