Specific Gravity

Written by Jerry Ratzlaff on . Posted in Dimensionless Numbers

Specific Gravity

Specific gravity ( \(SG\) ) (dimensionless number) is the density or ratio of any substance to another substance.  It sometimes may be called just gravity or relative density.  When calculating the specific gravity of a liquid or solid, water is normally the comparison (water has a specific gravity of 1).  

Even though two objects are the same size, their density may be different. This is expressed in how much more weight the object is in comparison to the same amount of water.  Likewise a gas is compared to air.

Specific Gravity formula

\(SG = \frac { \rho_s } { \rho_w  } \)          \( specific \; gravity   \;=\;   \frac { sample \; density } { water \; density  } \)

Where:

\(\rho_s\) (Greek symbol rho) = sample density

\(\rho_w \) (Greek symbol rho) = water density

\(SG\) = specific gravity

Solve for:

\(\rho_s = SG \rho_w  \)

$\rho_w = \frac { \rho_s } { SG  }

Specific Gravity conversion table

  • This is a Density Conversion
Specific Gravity Conversion Table
MultiplyByTo Get
  436995.7259 grain per cubic foot
  252.8910451 grain per cubic inch
  1 gram per cubic centimeter
  1e+15 gram per cubic kilometer
  1000000 gram per cubic meter
  0.001 gram per cubic millimeter
  1000000 gram per kiloliter
  1000 gram per liter
  1 gram per milliliter
  0.001 kilogram per cubic centimeter
  1e+12 kilogram per cubic kilometer
  1000 kilogram per cubic meter
  1e-15 kilogram per cubic micrometer
  0.000001 kilogram per cubic millimeter
  998.8473734 ounce per cubic foot
  0.578036674 ounce per cubic inch
  62.42796084 pound per cubic foot
  0.036127292 pound per cubic inch
  1 standard conditions
  1 specific gravity, water

 

Specific Gravity of materials Table

MaterialSpecific Gravity
Acetylene 0.0017
 Air, dry 0.0013
 Alcohol 0.82
 Aluminium 2.70
 Aluminium Alloy 356.0 2.68
 Aluminium Alloy 360.0 2.68
 Aluminium Alloy 364.0 2.63
 Ammonia Vapor 0.60
Antimony 6.68
 Balsa Wood 0.2
Barium 3.62
Barium sulfate 4.5
Boron 2.34
 Brass 8.48
 Cadmium 8.58
Calcium sulfate 2.96
Carbon 2.26
 Carbon dioxide 0.00198
Carbon monoxide 0.00126
 Cast iron 7.20
Caustic potash 2-044
Cement 3.15
Cerium 6.77
Cesium 1.873
 Chromium 7.03
Citric acid 1.665
Clay 2.6
 Copper 8.96
 Depleted uranium 19.1
Diesel fuel 0.84
 Epoxy resin 1.8 - 2.0
 Ethanol 0.78
Gasoline 0.70 - 0.76
Glass 2.40 - 2.70
 Gold 19.30
Grease 0.92 - 0.94
Hematite 5.26
Hydrogen 0.00009
Iron 7.87
Lead 11.35
Limestone 2.8
Melamine 1.8 - 2.0
Mercury 13.56
Natural Gas 0.59
Nickel 8.9
Nylon 1.12
Oak wood 0.75
Osmium 22.59
Oxygen 0.00143
Parrafin 0.80
Petrol (gasoline) 0.72
Phenolic 1.75 - 1.95
Platinum 21.5
Polyester 1.35 - 2.3
Polyurethane 1.11 - 1.25
Propane gas 1.55
PVC 1.36
Pyrite 5.02
Quartz 2.65
Rubber 0.96
Salt 2.165
Silicon 2.33
Soda ash 2.53
Sodium bicarbonate 2.16
Sodium sulfite 2.63
Steel, carbon 7.82
Steel, cold drawn 7.83
Steel, machine 7.80
Strontium 2.64
Sulfur 2.07
Table Salt 2.17
Tantalum 16.69
Tellurium 6.24
Terbium 8.27
Thallium 11.85
Thulium 9.32
Tin, pure 7.28
Titanium 4.506
Titanium, dioxide, Anatase 3.77
Tungsten 19.25
Tungsten, carbide 14.29
Uranium 18.7
Water 1
Water, sea salt 1.027
Ytterbium 6.97
Yttrium 4.47
Zinc 7.12
Zirconium 6.506
Zirconium silicate 3.85

Tags: Equations for Gravity