Relative density, or specific gravity, is the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. If the relative density is exactly 1 then the densities are equal; that is, equal volumes of the two substances have the same mass.

Specific gravity is a ratio of the density of a substance to the density of a reference substance, usually water. Since the density of water is one gram per cubic centimeter, you calculate specific gravity by dividing the density of a substance by one gram per cubic centimeter.

Density is defined as mass per unit volume. Specific gravity is the ratio of a material’s density with that of water at 4 °C (where it is most dense and is taken to have the value 999.974 kg m-3). It is therefore a relative quantity with no units.

The normal specific gravity ranges from person to person. Your urine specific gravity is generally considered normal in the ranges of 1.005 to 1.030. If you drink a lot of water, 1.001 may be normal. If you avoid drinking fluids, levels higher than 1.030 may be normal.

The density is directly related to the mass of the object (unit: usually in grams but can be measured in kilograms or pounds), so the specific gravity can also be determined by dividing the mass of the object by the mass of the water.

High specific gravity suggests that the urine is too concentrated. Conditions that cause high specific gravity include: dehydration. diarrhea or vomiting resulting in dehydration. congestive heart failure.

Significance and Use 4.1 Specific gravity is an important property of fluids being related to density and viscosity. Knowing the specific gravity will allow determination of a fluid’s characteristics compared to a standard, usually water, at a specified temperature.

Can temperature affect specific gravity? Yes, it can. When using water as a reference for establishing specific gravity, it is almost always assumed that the water is at 4°C, when it’s densest. Water itself becomes less dense as it becomes warmer until it evaporates and becomes steam vapor at boiling point.

When the specific gravity is defined based on water at 4°C, then the specific gravity is equal to the density of the liquid. However, if the specific gravity is expressed at different temperatures, it will no longer be equal to the density.

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Specific gravity varies with temperature and pressure; reference and sample must be compared at the same temperature and pressure or be corrected to a standard reference temperature and pressure. Substances with a specific gravity of 1 are neutrally buoyant in water.

Factors of heating time, heating temperature, warm mix additives and amount of virgin asphalt added to RAP were investigated. The factors included two warm mix additives, three mixing temperatures, three asphalt contents and three RAP sources for a total of 34 test conditions and 68 tests.

The molecules of different liquids have different size and mass. The mass and size of the molecules in a liquid and how closely they are packed together determine the density of the liquid. Just like a solid, the density of a liquid equals the mass of the liquid divided by its volume; D = m/v.

Abnormal specific gravity results could indicate: excess substances in the blood. kidney disease (high or low specific gravity can indicate an inability of the kidney tubules to function correctly) infection, such as a urinary tract infection.

Specific gravity bottles determine liquid densities by measuring the difference between an empty and filled bottle and dividing by an equal volume of water to find the specific gravity of the substance.

Wrestlers with a urine specific gravity ≤1.020 are considered euhydrated and may have their body composition assessed to determine their minimal weight for competition, whereas wrestlers with a urine specific gravity >1.020 are considered to be dehydrated and may not proceed to body-composition testing on that day.