The DC motor was the mainstay of electric traction drives on both electric and diesel-electric locomotives, street-cars/trams and diesel electric drilling rigs for many years. The introduction of DC motors and an electrical grid system to run machinery starting in the 1870s started a new second Industrial Revolution.
One acre is 43,560 sq ft. One half acre is 21,780 sq ft. However, that doesn't help most people much when trying to picture how large a lot is. Half acre lot is roughly:
the distance in feet around 1 square acre is 835 feet, that is if the property is exactly square if the sides are not square and of equal length the outside perimiter distance will change. 13 people found this useful.