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 feet by how many feet equals 1 acre? 43559.45382 ft = 1 acre. square root of 43559.45832 sq ft = 208.73 ft-The U.S. acre is actually an even 43,560 (66x660 or 1/8 mi. by 1/80th).The odd decimal comes from imp â¦ roper use of international feet in a U.S. survey acre. An international acre is 43,560 international feet (exactly 304.8mm each).ow many feet by how many feet equals 1 acre? 43559.45382 ft = 1 acre. square root of 43559.45832 sq ft = 208.73 ft-The U.S. acre is actually an even 43,560 (66x660 or 1/8 mi. by 1/80th).