The dimentsions of a solid iron cuboid are `4.4 m xx 2.6 m xx 1.0 m ` .It is melted and recast into a hollow cylindrical pipe of 30 cm inner radius and thickness 5cm .Find the length of the pipe.

Explanation

Length of solid iron cuboid 4.4 m
Breadth of solid iron cuboid =2.6 m
Height of solid iron cuboid = 1.0 m
Volume of oil cuboid = `4.4 xx2.6 xx1=11.44 m^(3)`
`=11.44 xx100xx100xx100 cm^(3)`
This cuboid is melted and recast in to a hollow cylinder
Volume of cuboid = volume of hollow cylinder
`11.44xx10^(6)=piR^(2)h-pir^(2)h`
`11.44xx10^(6)=pih(R_(2)-r^(2))`
`11.44xx10^(6)xx7=22xxh(35-30)(35+30)`
`h=(11.44xx10^(6)xx7)/(22xx5xx65)cm=(11440000xx7)/(22xx5xx65)` cm
=112000 cm =112 m
Hence length of pipe =112 m