Why does farming equipment require such low horsepower compared to your average car?

Question

Why does farming equipment require such low horsepower compared to your average car?

In: 114

Answer 1

I remember learning in Classical Physics in college that the horsepower to drive a car on a flat surface was directly proportional to the drag of the vehicle as well as the cube of the speed.

Therefore, if it took say 30hp to drive a minivan down the interstate at 50mph to then triple the speed to 150mph would require (150mph/50mph) * * 3 times more horsepower or… 3 * * 3. 3 cubed is (3 * 3 * 3=)27 times more horsepower. 30 x 27 = 810hp. No stock minivan has 810 hp so no stock minivan can reach 150mph.

A Ferrari, however, might have half the drag of the minivan and would require only 15hp to drive down the interstate at 50mph. 15 x 27 = 405hp, so only 405hp would be required for the Ferrari to maintain 150mph, which many Ferraris can produce.