Weight is calculated in Kgs (not mms)

calculate the volume x multiply by density then convert the units as you want mm, microns cm,...

65x65x5 = volume of a square plate 5 thick and 65 x65 section

Density = 7.85 x 10³ Kg/m³ = 7.85 T/m³

In meters, 0.065 x 0.065 x 0.005 x 7.85 ≈ 0.000166 tonnes = 0.166 kg = 166 grams.

The OP is asking for weight of an angle (L). All we are multiplying 65 with 65. Thus we are calculating weight of a square plate of 65 mm X 65 mm 5 thick.

Weight of an angle 65X 65 with web thickness of 5 will be (65 + 65 - 5)X5 X 1000 X7.8/1000000= 4.875 Kg per meter. (neglecting web end radius).

Here (65 + 65 - 5) is total length of web of 5 mm thick

5 is thickness of the beb

1000 is for 1 miter length of the angle.

7.8 density gms/cm^3 for steel.

Divided by 1000 to make mm^3 to cm^3

Divided by 1000 to make gms to kg.

But why to calculate. You have ready tables for all sections available in the market.

What is the material? Steel? Aluminium? GFRP?

Helo

I think the basic approach is to find the volume of the given section per unit running length (either in per meter or per feet). L x b x H. It is preferbale to arrive at the volume in the same unit at which the density of the material is normally being given. I think the density is generally given in gms/cubic centimeters. So you should arrive at the volume in cubic centimeters in such a case.

Step 2:- When you know the material then find its density from standard tables

Step 3:- Then calculate the weight :- volume (say in cm3) x density (gms / cm3) this will give you the weight of the section per unit length

Step 4: multipy the arrived weight per unit length with the actual length of your section.

alternate option:- Now a days the weight of the standard sections have been tabulated and available in many technical handbooks. You can straight away refer from these handbooks.

Regards

Ramesh

let us assume the material is steel (since value 7.85 is used)

weight = volume x density

= 6.5 cm x 6.5 cm x 0.5 cm x 7.85 gms / cm3

= 165.83 gms

This way we can calculate for different materials with different densities.

Basically we need to convert all the dimensions its to same metric unit.

Correction to my earlier post....

When I read the body of the OP I was thinking of a small square of material, rather than an angle shape of some length.

W = (l₁ + l₂ -t)(t)(ρ)(L); where l₁ and l₂ are the leg dimensions, t is the thickness, ρ is the density, and L is the length. In the given example, it works out to 4.9 kg per meter of length.

Lets get really picky - you guys are all calculating the mass, he asked for the weight! Albeit in weird units.

Grand Unification theory in the singularity area?

Here all the laws will collapse so mass, weight, length all will be same (none will exist )

This is my GUT feeling.