A tractor is hauling a large trailer with a the load of mealies upwards on an incline or slope of 1 in 20 .The mass of the trailer is 4,5t and the load is 20t. The tractive resistance due to friction and the road surface is 450N/t. A strong wind is blowing directly from the front with a force of 300N per square metre of projected area, and the effective projected area of the trailer is 2.5m × 2m .The constant speed of the trailer is 20km/h .calculate:
1.The force exerted by the towbar of the tractor.
2. The workdone by the tractor in 10 minutes.
3.The power needed on the crowbar.