E₀ + E1

x2 = ---------- KT

d

Suppose that the positive carriers are produced at a uniform rate of q per second for unit distance between the plates. The number of positive carriers which reach B during a half alternation consists of two parts:

(1) One half of those carriers which are produced within the distance x1 of the plate B. This number is equal to

1

--- x1 qT

2

(2) All the carriers which are left within the distance x1 from B at the end of the previous half alternation. The number of these can readily be shown to be

1 x1