Question

A slab of iron whose dimensions are $60cm\times 20cm\times 28.26cm$ is used to cast an iron pipe . The outer diameter of the pipe is $10cm$ . If the wall of the pipe is $1cm$ thick . Calculate the length of the pipe that can be cast from the slab . (Use $\pi =3.14$)

Answer 1

Dimension of rectangular slabe$=60cm\times 20cm\times 28.26cm$

width of iron pipe$=1$cm

Outer diameter$=10cm$, outer radius(R)$=5$cm

Inner radius$\left(r\right)=$R-width

$=5-1=4$cm

Let length of wire be $h$

volume of iron pipe $=\pi (R^2-r^2)h$

$=3.14(25-16)\times 4$

$=3.14\times 9\times 4$

Volume of iron slab$=$ volume of iron pipe

$60\times 20\times 28.26=3.14\times 9\times h$

$h=\frac{60\times 20\times 28.6}{3.14\times 9}$

$h=1200cm=12m$.