Question

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.

Answer 1

Given:

Inner diameter = 24cm

Outer diameter = 28cm

h = 35cm

Mass of 1 cm³ of wood = 0.6gm

We have to find the mass of the pipe.

In this problem the inner and outer diameter of the pipe is given. Let us first find out the radius.

Inner radius (r) = 12cm

Outer radius (R) = 14cm

Volume of the hollow pipe = `pi (R^2 - r^2 ) h`

`= 22/7 xx ( 14^2 - 12^2 ) xx 35 `

`= 22 xx 5 xx 2 xx 26`

` = 5720  cm ^3`

It is given that,

1 cm³ of wood weighs 0.6gm

Therefore, 5720  cm³  of wood will weigh  5720 × .6 = 3432gm

 = 3.432kg

Therefore, weight of the wooden pipe = 3.432kg