Q14 of 44 Page 14

A godown building is in the form as shown in the adjoining figure. The vertical cross-section parallel to the width side of the building is a rectangle of size 7 m x 3 m mounted by a semicircle of radius 3.5 m. The inner measurement of the cuboidal portion are 10 m x 7 m x 3 m. Find the

(i) the volume of the godown, and


(ii) the total internal surface area excluding the floor.


(i) Volume of godown = Volume of cuboid +volume of cylinder


Volume of cuboid = l × b × h = 10 × 7 × 3 = 210 m3


Volume of cylinder = πr2h = = 385 m3


∴ Volume of godown


= 210 + 192.5


= 402.5 cm3


(ii) Internal Surface Area of a godown excluding the floor


the total surface area of the cylinder




= 6 × 17 + 22 × 0.5 × 13.5


= 102 + 148.5


= 250.5 cm2


Hence, internal surface area of godown excluding floor is 250.5cm2


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