Question

Earth's lower atmosphere contains negative and positive ions that are produced by radioactive elements in the soil and cosmic rays from space. In a certain region, the atmospheric electric field strength is 102 V/m and the field is directed vertically down. This field causes singly charged positive ions, at a density of 885 cm-3, to drift downward and singly charged negative ions, at a density of 518 cm-3, to drift upward (see the figure). The measured conductivity of the air in that region is 2.36 × 10-14 (Ω-m)-1. Calculate (a) the magnitude of the current density and (b) the ion drift speed, assumed to be the same for positive and negative ions.

Answer 1