What Does Unit Weight (kN/m^3) Mean?

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Unit weight, expressed in kN/m^3, refers to the weight of a material per unit volume, which differs from density measured in kg/m^3. The unit weight of aluminum is stated as 24 kN/m^3, which translates to the weight of a cubic meter of aluminum under standard gravity. This value can seem inconsistent with aluminum's density of 2700 kg/m^3, as weight and mass are distinct measurements; weight is a force measured in Newtons. The relationship between density and unit weight is defined by the equation gamma = rho * g, where gamma is unit weight, rho is density, and g is the acceleration due to gravity. Understanding this distinction is crucial, especially in fields like engineering and construction.
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What Does Unit Weight (kN/m^3) Mean?
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What Does Unit Weight (kN/m^3) Mean?
Hello

This is a really silly question but I have doubted myself and I was wondering if anyone could help.

I have been given the following information:-
Unit Weights.png
I am trying to understand what it means when the title states Unit Weights?

I thought these were density but density is kg/m^3 - whereas these units are kN/m^3

What does it mean to say that the unit weight of Aluminium is 24 kN/m^3

Can someone help?

Thank you.
 
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Seems to be weight per volume under standard gravity. The aluminium value seems off though based on aluminium having a density of 2700 kg/m^3.
 
tomtomtom1 said:
What does it mean to say that the unit weight of Aluminium is 24 kN/m^3

Can someone help?

Thank you.

Why wouldn't that mean that a cubic metre of aluminium weighs 24kN?

Weight being a force is measured in Newtons, as opposed to mass which is measured in kilograms.
 
Unit weight simply refers to weight per unit volume. It is often denoted as lower case gamma, If rho is the density, then gamma = rho * g.
 
Isn't Unit Weight and Density the same thing?
 
Only if mass and weight are the same thing (which they are not).
 
tomtomtom1 said:
Isn't Unit Weight and Density the same thing?
If and when you work on constructing a colony on Mars, you'll discover the difference.
 
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