1. What is Specific Gravity?

Specific Gravity (SG) is a dimensionless quantity defined as the ratio of the density of a substance to the density of water at a specified temperature. It indicates whether a substance will float or sink in water.

2. How Does the Calculator Work?

The calculator uses the specific gravity formula:

Where:

• \( \rho \) — Density of the substance (kg/m³)
• \( \rho_{water} \) — Density of water (typically 1000 kg/m³ at 4°C)
• \( SG \) — Specific Gravity (dimensionless)

Explanation: The formula compares the density of a material to the density of water. Values less than 1 indicate the material will float in water, while values greater than 1 indicate it will sink.

3. Importance of Specific Gravity

Details: Specific gravity is used in many industries including brewing, gemology, petroleum, and chemical engineering. It helps identify substances, determine purity, and predict buoyancy.

4. Using the Calculator

Tips: Enter the density of your substance in kg/m³ and the reference water density (default is 1000 kg/m³). Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the specific gravity of water?
A: Pure water has a specific gravity of exactly 1 at standard temperature and pressure (4°C, 1 atm).

Q2: How does temperature affect specific gravity?
A: Since density changes with temperature, specific gravity measurements should specify the temperature at which they were taken.

Q3: What are typical specific gravity values?
A: Most rocks and metals have SG > 1, while wood and many plastics have SG < 1. For example, gold has SG ~19.3, while cork has SG ~0.24.

Q4: Can specific gravity be less than zero?
A: No, specific gravity is always a positive number since density cannot be negative.

Q5: How is specific gravity different from density?
A: Density has units (kg/m³), while specific gravity is dimensionless. SG compares a material's density to water's density.