Derivation of Boltzmann distribution for 1-dimensional potential

p(h):pressure
n(h):number of particles in unit volume
F(h):force applied to the each particle
U(h):potential energy of the particle

From equation of state, we obtain:
p(h)V=NRTp(h)=n(h)kbT

Considering equilibrium of forces in the gas between h and h+dh, we obtain:
Sp(h+dh)+n(h)F(h)Sdh=p(h)Sp(h+dh)+n(h)F(h)dh=p(h)p(h+dh)p(h)dh=n(h)F(h)dpdh=n(h)F(h)

By substituting (1) to (2),we can derive differential equation (3). kbTdndh=n(h)F(h) ODE (3) can be solved by dividing both sides by n. 1ndndh=F(h)kbT Integrating both sides by h results in following. 1ndn=1kbTF(h)dh 1ndn=1kbTF(h)dh log(n)=1kbTF(h)dh n(h)=exp(F(h)dhkbT)=exp(U(h)kbT) where U(h) is the potential energy of each particle at height h.

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