Surface Area of Prisms OCR Stage 8 A
- Slides: 7
Surface Area of Prisms OCR Stage 8
A Prism Cylinder Cuboid Trapezoid Prism Triangular Prism Surface Area of Prism = Total of ALL individual surfaces
Area Formulae r h Area Circle = π x r 2 b Area Rectangle = Base x height a h b Area Trapezium = ½ x (a + b) x h h b Area Triangle = ½ x Base x height
Surface Area Cuboid Area A = b x h = 7. 2 x 5. 3 = 38. 16 cm 2 C 5. 3 cm B A Area B = b x h = 5. 3 x 10. 6 = 56. 18 cm 2 Area C = b x h = 7. 2 x 10. 6 = 76. 32 cm 2 10. 6 cm 7. 2 cm BUT there are 2 A’s, 2 B’s and 2 C’s 2 x A = 38. 16 x 2 = 76. 32 cm 2 2 x B = 56. 18 x 2 = 112. 36 cm 2 2 x C = 76. 32 x 2 = 152. 64 cm 2 Total Surface Area = 341. 32 cm 2
Surface Area of Cylinder Cross-sectional Area = π x r 2 = π x 32 = 28. 2743…. . cm 2 3 cm 2 x Circles = 2 x 28. 2743… = 56. 5486… cm 2 5 cm 5 2πr Curved surface area = 5 x 2 x π x 3 = 94. 2477…. cm 3 Total = 56. 5486… + 94. 2477. . = 154. 796. . cm 2 = 154. 8 cm 2
Surface Area - Trapezoid Prism Cross-sectional Area = ½ x(a + b) x h = ½ x (6. 3 + 1. 7) x 4. 9 = 19. 6 cm 2 2 x A = 19. 6 x 2 = 39. 2 cm 2 2 x B = 8. 2 x 4 x 2 = 65. 6 cm 2 1 x C = 8. 2 x 6. 3 = 51. 66 cm 2 1 x D = 8. 2 x 1. 7 = 13. 94 cm 2 Total Surface Area = 170. 4 cm 2 6. 3 cm 4. 9 cm A 1. 7 cm C B 4 cm 8. 2 cm D (the base)
Surface Area Triangular Prism Cross-sectional Area = ½ x b x h = ½ x 8. 6 x 4. 1 = 17. 63 cm 2 C [rear] 4. 1 cm DO NOT ROUND! 2 x A = 17. 63 x 2 = 35. 26 cm 2 1 x B = 6. 2 x 9. 53 = 57. 18 cm 2 1 x C = 4. 1 x 6. 2 = 25. 42 cm 2 1 x D = 8. 6 x 6. 2 = 53. 32 cm 2 Total Surface Area = 171. 48 cm 2 4. 9 cm A 9. 53 cm B 6. 2 cm 8. 6 cm D [the base]
