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:
How many acres in a section? An acre measures 43,560 square feet which is roughly 208.71 feet on a side. A section (one square mile) measures 27,878,400 square feet. Divide 27,878,400 by 43,560 and that equals 640 acres in a section. A half (1/2) section is 320 acres.