Question

4.) A John Deere tractor is pulling a 28-foot tandem disk at a speed of 5 mph. The John Deere FMO book states the draft per unit width for a medium weight tandem disk in heavy (clay loam) soil as 300 lbs per foot. What is the minimum horsepower required for this tractor? 20 pts

Answer 1

The formula for power required in this case is given by:

Power = width x speed x draft per unit width.

In the above question, width = 28 feet, speed = 5 mph and draft per unit width = 300 lbs/feet.

Therefore, Power = 28*5**300 = 42000 lbs.mph

Conversion factor from horsepower to lbs.mph is 374.85.

Therefore the minimum power required for this tractor is 112 hp.