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Specific Gravity Formula:
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Specific Gravity (SG) is a dimensionless quantity that represents the ratio of the density of a substance to the density of a reference substance (typically water at 4°C). It indicates whether a substance will float or sink in water.
The calculator uses the Specific Gravity formula:
Where:
Explanation: The formula calculates how many times denser or lighter a liquid is compared to water. A value less than 1 indicates the liquid is lighter than water and will float, while a value greater than 1 indicates it's denser and will sink.
Details: Specific gravity is crucial in various industries including petroleum, brewing, pharmaceuticals, and chemistry. It helps identify substances, determine concentration of solutions, assess purity, and predict buoyancy behavior.
Tips: Enter the density of the liquid in kg/m³ and the density of water reference (default is 1000 kg/m³). Both values must be positive numbers. The result is a dimensionless quantity (unitless).
Q1: Why is water used as the reference substance?
A: Water is used as the reference because it's abundant, well-studied, and has a density of exactly 1000 kg/m³ at 4°C, making calculations straightforward.
Q2: What are typical specific gravity values?
A: Most liquids have specific gravity values between 0.7-1.5. Water has SG = 1, gasoline ~0.7, seawater ~1.03, and mercury ~13.6.
Q3: Does temperature affect specific gravity?
A: Yes, since density changes with temperature, specific gravity measurements should specify the temperature at which they were taken for accurate comparisons.
Q4: How is specific gravity different from density?
A: Density is an absolute measurement (mass/volume) with units, while specific gravity is a relative measurement (ratio) without units that compares density to water.
Q5: Can specific gravity be used for solids and gases?
A: Yes, specific gravity can be calculated for any material by comparing its density to the density of water, though it's most commonly used for liquids.