All Problems Electric Current
Problem 3.214
The air between two closely located plates is uniformly ionized by ultraviolet radiation. The air volume between the plates is equal to \(V=500 \mathrm{~cm}^{3}\), the observed saturation current is equal to \(I_{s a t}=0.48 \mu\) A. Find: (a) the number of ion pairs produced in a unit volume per unit time; (b) the equilibrium concentration of ion pairs if the recombination coefficient for air ions is equal to \(r=1.67 \cdot 10^{-6} \mathrm{~cm}^{3} / \mathrm{s}\)
3.214. (a) \(\dot{n}_{i}=I_{\text {sat }} / e V=6 \cdot 10^{9} \mathrm{~cm}^{-3} \cdot \mathrm{s}^{-1} ;\) (b) \(n=\sqrt{n_{i} / r}=\) \(=6 \cdot 10^{7} \mathrm{~cm}^{-3}\)