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Homework Help: Atmospheric Density, exponential decay derivation

  1. Nov 19, 2007 #1
    I've read my lecture notes about 100x but can't even begin to see where this derivation can come from. A previous derivation was the equation
    dP/dz = -gρ
    (P = pressure, z = distance, g= acc due to grav, ρ = density)

    If atmosphere can be treated as an isothermal ideal gas of constant mean molecular mass m, show that density drops exponentially with height,
    ρ= [ρ0]e^-z/h
    where h is a constant*

    later i worked through to find it was the scale height ~8.5km but the value is unknown for this question.
  2. jcsd
  3. Nov 19, 2007 #2
    bump 2pm deadline ...
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