Question

A steel rectangular tube has outside dimensions of 150 mm x 50 mm and a wall thickness of 4 mm. State the inside dimensions, the area of its cross section, and the weight of a piece 1.22 m long.

Answer 1

inside dimension
`= 142 mm * 42 mm`

cross section area
`= 7.5* 10^(-3) m^2`

mass of 1.2 meter log steel
`= 1.843* 10^(-3) \rho`

Step-by-step explanation:

given data:

Outside dimension of steel rectangular
`= 150 mm* 50mm`

Thickness = 4 mm

Long = 1.22 m

inside dimension will be
`= (150- 8)mm * ( 50-8)mm`

`= 142 mm * 42 mm`

cross section area
`= 150* 50 mm^2`

`= 7500* 10^(-6) m^2`

`= 7.5* 10^(-3) m^2`

let the density be assumed as \rho

mass of 1.2 meter log steel will be
`= 1.2  * (7.5* 10^(-3) -  0.142* 0.048)* \rho`

`= 1.843* 10^(-3) \rho`