When James Watt was marketing his steam engine, he needed to visualize its advantage over traditional sources of energy.
He calculated how much weight an average horse could lift per minute by driving a water pump, and designated this unit of power as horsepower. Then the power of steam engines, expressed in horsepower, immediately began to indicate how many times more efficient the machine is than a horse.
By the way, according to scientists' calculations, a horse can work with a maximum load of almost 15 horsepower for a short time.
