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Question
A cylindrical container with internal diameter of its base 20 cm, contains water upto a height of 14 cm. Find the area of the wet surface of the cylinder.
Solution
Inner diameter of base = 20cm
Radius = 10cm
Area of the wet surface of the cylinder
= Inner curved area of cylinder + area of base
= 2πrh + πr2
= 2π x 10 x 14 + π(10)2
= 280π + 100π
= 380π
= 1194 cm2
∴ Area of the wet surface of the cylinder is 1194 cm2.
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