What is the unit weight of water in kN/m³ and its density in slug/ft³ and kg/m³?

To find the unit weight of water in kN/m³, we start with the given unit weight of water as 62.4 lb/ft³.

First, we can convert lb/ft³ to kN/m³ using the following conversions:

• 1 lb is approximately equal to 0.00444822 kN.
• 1 ft³ is equal to 0.0283168 m³.

Now, performing the conversion:

   Unit Weight in kN/m³ = 62.4 lb/ft³ * (0.00444822 kN/lb) * (1 ft³ / 0.0283168 m³)
   Unit Weight in kN/m³ ≈ 62.4 * 0.00444822 / 0.0283168
   Unit Weight in kN/m³ ≈ 9.81 kN/m³

Next, let’s determine the density of water in slug/ft³. The density of water in lb/ft³ can be related to slugs using the conversion:

• 1 slug is equivalent to 32.174 lb.

So, we can convert the unit weight:

   Density in slug/ft³ = 62.4 lb/ft³ / 32.174 lb/slug
   Density in slug/ft³ ≈ 1.94 slug/ft³

Lastly, to find the density in kg/m³, we will convert lb/ft³ to kg/m³ with the following conversions:

• 1 lb is approximately equal to 0.453592 kg.
• 1 ft³ is equal to 35.3147 L, with 1 L = 0.001 m³.

Using this information, we can convert:

   Density in kg/m³ = 62.4 lb/ft³ * (0.453592 kg/lb) / (0.001 m³/L * 35.3147 L/ft³)
   Density in kg/m³ ≈ 999.97 kg/m³

In summary:

• Unit weight of water: approximately 9.81 kN/m³
• Density of water: approximately 1.94 slug/ft³
• Density of water: approximately 1000 kg/m³