posted by Harold on .
A 1500 kg truck travels at 30m/s. It faces a force of 400 N from air resistance, what is the car's average power output?
Is the answer 675 kw?If not please help me in any way you can,by showing the formula you used.
Regardless of the weight of the truck, the average power on a level road is wind resistance x velocity (neglecting engine piston and rolling friction, and transmission losses). That number is 30 x 400 = 12,000 W
At that speed (67 mph), overcoming air resistance is where most of the power goes. 400 N (about 100#) sounds rather low for the air resistance of a truck at that speed.