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Last updated at Dec. 8, 2016 by Teachoo

Transcript

Ex 13.1, 2 A vessel is in the form of a hollow hemisphere mounted by a hollow cylinder. The diameter of the hemisphere is 14 cm and the total height of the vessel is 13 cm. Find the inner surface area of the vessel. Inner surface area of the vessel = Curved surface area of hemisphere + Curved surface area of the cylinder Curved Surface area of hemisphere Diameter of hemisphere = 14 cm radius of hemisphere = r = 14/2 = 7 cm Curved surface area of hemisphere = 2 ๐๐2 = 2 ร22/7ร(7)2 = 2ร22/7ร7ร7 = 2ร22ร7 = 308 cm2 Curved surface area of cylinder Curved Surface area of cylinder = 2๐๐โ Radius of cylinder = radius of hemisphere = r = 7 cm Height of cylinder = Total height โ Radius of hemisphere = 13 โ 7 = 6 cm Curved Surface area of the cylinder = 2๐๐โ = 2ร22/7ร7ร6 = 2 ร22 ร6 = 264 cm2 Inner surface area of the vessel = Curved surface area of hemisphere + Curved surface area of the cylinder = 308 + 264 = 572 cm2 Hence, Inner surface area of vessel = 572 cm2

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Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.