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A solid is in the form of a right circular cylinder, with a hemisphere at one end and a cone at the other end. The radius of the common base is 3.5 cm and the heights of the cylindrical and conical portions are 10 cm and 6 cm, respectively. Find the total surface area of the solid.( use π = \(\frac{22}7\)) |
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Answer» Height of cylinder (h) = 10 cm Height of conical part = 6 cm Slant height of cone (l) = \(\sqrt{r^2 + h^2}\) ⇒ l = \(\sqrt{3.5^2 + 6^2}\) ⇒ l = 48.25 cm Curved surface area of cone = πrl = π (3.5) (48.25) = 76.408 cm2 …(1) Curved surface area of cylinder = 2πrh = 2π (3.5) (10) = 220 cm2 …(2) Curved surface area of hemisphere = 2πr2 = 2π (3.5)2 = 77 cm2 ….(3) ∴ Total curved surface area = Curved surface area of(cone + cylinder + hemisphere) = 76.408 + 220 + 77 = 373.408 ∴ Total surface area of solid = 373.408 cm2 |
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