Derivation of the Equation

Tramper is assumed to be a symmetrical object of total surface area S, totally immersed in leatherwood.

Area of one side is .

Total volume of leatherwood displaced (sum of incremental volumes) is where d is distance travelled in leatherwood field.

By Archimedes,apparent loss of mass M of tramper, where D is mean field density.

However, because of the extremely abrasive nature of the medium, a proportion L of this M is actually lost.

.where w and a are dependent on the state of the leatherwood and the armour of the tramper respectively.

L can be expressed as a sum,

L = L* + nm...2.where L* is mass of neutral particles lost; n is number of excess electrons lost; and m is mass of one electron.

Define a quantity F, the efficiency of excess electron production.

Substituting and rearranging in 1. and 2.,

Therefore total charge Q on tramper is

DSd where c is charge on one electron.