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=NRT→p(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)S→p(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=−1kbT∫F(h)dh ↔∫1ndn=−1kbT∫F(h)dh ↔log(n)=−1kbT∫F(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.
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=NRT→p(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)S→p(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=−1kbT∫F(h)dh ↔∫1ndn=−1kbT∫F(h)dh ↔log(n)=−1kbT∫F(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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