Quantcast

Pentagon Weight

`M = 1/4 * sqrt( 5*(5 + 2* sqrt(5)))* s^2 * h * mD`
`(s)"Length of Pentagon Side"`
`(h )"Height of Pentagon"`
`(mD)"Mean Density"`

This Weight of a Pentagon calculator computes the weight of a regular /attachments/11930118-2748-11e6-9770-bc764e2038f2/PentagonVolume.JPGpentagon shaped objects with 5 equal sides of length, a height and the density of material. 

INSTRUCTIONS: Choose units and enter the following:

  • (s) Length of Pentagon Sides
  • (h) Height of Pentagon Shape
  • (mD) Mean Density of Material

Weight of a Pentagon (M): The mass / weight is returned in kilograms.   However, this can be automatically converted to compatible units via the pull-down menu.

The Math / Science

The calculator first computes the volume of the pentagon shape.

The formula for the mass of a pentagon is:

    M =¼•√(5+2•√5)•s2•h•mD 

where:

  • M = Mass of Pentagon 
  • s = Side Length
  • h = Height
  • mD = Mean Density of Material

A regular pentagon has five equal sides and equal angles.  A pentagon volume is a pentagon shaped object with a regular pentagon cross-section (area) and perpendicular height.

Mean Density Table

Common Mean Densities in Kilograms per Meter Cubed (kg/m3)

Fluids

  • Pure Water - 1,000  
  • Seawater - 1,022  
  • Milk - 1,037 
  • Olive Oil - 860
  • Cement Slurry - 1,442 

Fuels

  • Diesel Fuel - 885 
  • Crude Oil - 870 to 920  
  • Fuel Oil -  890  
  • Ethanol - 789  
  • Gasoline (petrol) - 737 
  • Propane - 493 
  • Liquid Natural Gas - 430 to 470 

Market-Ready Grains

 

Metals

Earthen

  • Concrete - 2,371
  • Dirt - 1,250
  • Fire Clay - 1,362
  • Glass - 2,500
  • Granite - 2,691
  • Sand (dry) - 1,602
  • Sand (wet) - 2,082
  • Sandstone - 2,323

Synthetic

  • Bakelite - 1,362
  • Carbon Fiber - 2,000

Organic

  • Balsa - 170
  • Cork - 240
  • Mahogany - 545
  • Oak - 760
  • Pine - 539
  • Rubber - 1,522
                 Mean Density Lookup Function

Mean density is scientifically volume divided by mass.  There are  various unit for density adopted by cultures and industries. Common units for density included the following:

  • kilograms per cubic meter (kg/m3)
  • grams per cubic centimeter (g/cm3)
  • grams per liter (g/L)
  • pounds per cubic feet (lb/ft3)
  • ounces per cubic inch (oz/in3)
  • pounds per barrel (lb/bbl)
  • pounds per bushel (lb/bu)

If you want to identify a material by its density, use the Density Within Range tool.


Weight is technically the downward force that a mass exerts based on the force of gravity and the mass of the object.  On the surface of the Earth, mass and weight are often interchanged.  In some places, objects are sold by the gram (mass), and in other locations, the same objects are sold by the ounce (weight).

The Weight Calculators use the dimensions of an object and its shape to compute the objects volume.  They then apply a density associated with a material to estimate the objects weight.

Weight Calculators