Question

The outer diameter of a metallic pipe is 18cm and the thickness of the pipe is 2 cm and the height is 4 cm. Find the surface area of the metallic pipe???

solve this


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Answer 1

Find the outer radius:

Radius = Diameter ÷ 2

Outer Radius = 18 ÷ 2 = 9 cm


Find the outer surface area:

Outer surface area = 2πrh

Outer surface area = 2π(9)(4) = 72π cm²


Find the inner radius:

Thickness = 2 cm

Inner radius = 9 - 2 = 7 cm


Find the inner surface area:

Inner surface area = 2πrh

Inner surface area = 2π(7)(4) = 56π cm²


Find the area of both ends:

Area of 2 ends of the pipe = 2[ π(9)² - π(7)²] 64π cm²


Find the total surface area:

Total surface area =  72π  + 56π  + 64π

Total surface area  = 192π

Total surface area = 603.43 cm²


Answer: 603.43 cm²