Question

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

Answer 1

Answer:

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