The inner diameter of a cylindrical wooden pipe is 24 cm and its outer diameter is 28 cm. The length of the pipe is 35 cm. Find the mass of the pipe, if 1 cm3 of wood has a mass of 0.6 gm.
Given,
Inner diameter of cylindrical pipe = 24 cm
So, inner radius = 
Outer diameter of that pipe = 28 cm
So, outer radius =
Length of pipe = 35 cm
Volume of pipe = π(R2 – r2) = 
= 22×26×2×5 = 5720 m3
1 cm3 wwod has mass = 0.6 gm
∴ 5720 cm3 wood has mass = 5720 ×0.6 = 3432 gm = 3.432 kg.
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