What Is Specific Gravity? How Do You Measure It?
Specific gravity is also called relative density.
It’s used to define the weight or density of a substance as compared to the density of an equal volume of a reference substance at a specified temperature.
Specific gravity for liquids is almost always measured with a reference point to water with the temperature at 4 °C or 39.2 °F.
Specific gravity for gases is almost always measured in reference to air at a room temperature of 20 °C or 68 °F.
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Specific Gravity Is A Measurement
Specific gravity is the ratio of the density of a substance to the density of a reference substance. (source ◳)
In most of the cases the reference substance is water for liquids or air for gases. Specific gravity represents a ratio and is therefore dimensionless. (source ◳)
How To Measure Specific Gravity
We can use specific gravity to determine the density of the substance.
The density of liquid water is 0.997, so if we weigh a cup of water and then weigh the cup of water after we have added a substance, we can determine the density of the water by using the formula:
weight of water – weight of water + substance
Specific Gravity For Solids And Liquids
Specific gravity is a measure of the density of a substance, which is useful for distinguishing between a solid and a liquid.
The more dense a substance, the more solid it is.
Water is the most dense liquid known. We know that water has a specific gravity of 1.000.
Dense substances have a specific gravity of 1.000 or more. So dense substances are called solids, and substances that are less dense are called liquids.
Foods You Can Measure With Specific Gravity
We only have one food in our tool that has a measurement for it
Foods in our nutrition tool
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We currently have just a few foods in our nutrition tool that measure specific gravity.
Here's our short list of foods that measure Specific Gravity.