The hydraulic braking system for the truck and trailer is set to produce equal braking forces for the two units. if the brakes are applied uniformly for 4 seconds to bring the rig to a stop from a speed of 32 mi/hr down the 8-percent grade, determine the magnitude of the force p in the coupling between the trailer and the truck. the truck weighs 23,000 lb and the trailer weighs 19,000 lb. 32 mi/hr 100 p = lb the tolerance is +/-2%