Specific Gravity

All right, the next one we're going to talk about is specific gravity. Specific gravity is actually fairly straightforward. It is normalized density. So, it is the density of what I'm working with the substance, right? And I normalize it to the density of water at 4 degree C, which is roughly 999 kg per meter cube. What's the unit? Well, it's unitless, right? That's one of the advantages. So, if I want to convert the specific gravity from one unit system to another, then I don't have to worry about it. Number one. Number two. Why do we want to use this is that? If I have, let's say, a high-density liquid like mercury, which is 13,600 roughly kilogram per meter cube, right, if I divide that by 999, so I'm going to get my corresponding specific gravity is 13.6 roughly. So, this is much easier to deal with. That's why we use this.