Question

A rear-end collision occurs between two vehicles on a 6% downhill section of a highway. A 430 ft. skidmark was left. Based on the damage to the two vehicles, accident investigators determined that the relative impact velocity was about 10 mph. If the lead vehicle was itself moving at 20 mph when it was hit, estimate the speed of the back vehicle when the driver first applied the brake began leaving skidmarks. Assume the AASHTO deceleration rate.

Answer 1