A 675-N Marine in basic training climbs a 8.5-m vertical rope at a constant speed in 7.75 s. What is his power output? W [-/1 Points SERPSE10 8.5.OP.018. As a van travels along a level stretch of road with constant speed, most of the power developed by the engine is used to compensate for the energy transformations due to friction forces exerted on the van by the air and the road. If the power developed by the engine is 3.00hp, calculate the total friction force acting on the van (in N ) when it is moving at a speed of 32 m/s. One horsepower equals 746 W. N