volume of prisms and cylinders objective: be able to work out the volume of a prism and a cylinder

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Volume of prisms and cylinders Objective: Be able to work out the volume of a prism and a cylinder.

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Page 1: Volume of prisms and cylinders Objective: Be able to work out the volume of a prism and a cylinder

Volume of prisms and cylinders

Objective: Be able to work out the volume of a prism and a cylinder.

Page 2: Volume of prisms and cylinders Objective: Be able to work out the volume of a prism and a cylinder

Volume of a prism

• the volume of a rectangular prism is:

length

width

height

Volume = length x width x height

Page 3: Volume of prisms and cylinders Objective: Be able to work out the volume of a prism and a cylinder

Volume of a prism

• What is the volume of a rectangular prism with dimensions 10 cm, 8 cm and 5 cm.

Area of Base= 10 cm x 8 cm = 80 cm2

5 cm

10 cm8 cm

Page 4: Volume of prisms and cylinders Objective: Be able to work out the volume of a prism and a cylinder

Volume of a cylinder

• Volume of a cylinder is the area of the cross-section times the height

Height h

Volume of cylinder = πr2h

Radius r

Page 5: Volume of prisms and cylinders Objective: Be able to work out the volume of a prism and a cylinder

Find the volume of a cylinder with radius 10 cm and height 20 cm

Area of base = πr2= π x 102= π x 100= 100 π cm2

Height 20cm

Volume of cylinder = π r2h

= π x 100 x 20

= 2000 π cm3

Radius 10cm

Volume of prism = B x height

Page 6: Volume of prisms and cylinders Objective: Be able to work out the volume of a prism and a cylinder

Find the volume of this prismSince the base is a triangle,

B=½ b h

B = ½ x 5 x 4

= 10 cm2

4cm

5cm

Volume of prism = 10 x 14

= 140 cm3

14cm

Volume of prism = B x height of the prism

Page 7: Volume of prisms and cylinders Objective: Be able to work out the volume of a prism and a cylinder

Find the volume of this prism

The base is a parallelogram

B = 6 x 7

= 42 cm2

7cm

6cm

Volume of prism = 42 x 15

= 630 cm3

15cm

Volume of prism = B x height of the prism