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Jeans Length Using Speed of Sound

The Jeans length is the critical radius for instability of a collapsing thermalized cloud of self­gravitating gas.

The Jeans length is proportional to the sound speed times the square root of the reciprocal of the mass density.

Formula

QuantityVariable[Subscript["R", "J"], "Length"] == Sqrt[Pi]*QuantityVariable["c", "SoundSpeed"]*Sqrt[Quantity[1, "GravitationalConstant"^(-1)]/QuantityVariable["ρ", "MassDensity"]]

symbol description physical quantity
RJ Jeans length "Length"
c sound speed "SoundSpeed"
ρ mass density "MassDensity"

Forms

Examples

Get the resource:

In[1]:=
ResourceObject["Jeans Length Using Speed of Sound"]
Out[1]=

Get the formula:

In[2]:=
FormulaData[ResourceObject["Jeans Length Using Speed of Sound"]]
Out[2]=

Use some values:

In[3]:=
FormulaData[
 ResourceObject[
  "Jeans Length Using Speed of Sound"], {QuantityVariable[
   "c","SoundSpeed"] -> Quantity[3129.28`6., ("Meters")/("Seconds")], 
  QuantityVariable[
\!\(\*SubscriptBox[\("R"\), \("J"\)]\),"Length"] -> 
   Quantity[2.624`4.*^14, "Kilometers"]}]
Out[3]=

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