A 1500 kg Prius and a 2400 kg Ford F150 pickup truck are approaching an unmarked intersection. The Prius is headed north, and the pickup is headed east, they both fail to stop. The Prius%u2019s onboard computer shows that its speed at the time of impact is 13.5 m/s. The truck%u2019s speed is unknown. The accident site shows a streak on the road, where the cars slid after they meshed together. This mark 9.5 m long, but the police at the accident site failed to observe the angle of this skid. The cars have average-condition tires, and the coefficient of kinetic friction of rubber on this road%u2019s surface is 0.65. You are the expert witness.
a) What is the speed of the cars right after they mesh together (but before they skid to a stop)?
b) What is the angle of the skid mark on the road (you will send your assistant out to verify this to show you are a qualified witness)?
c) What is the speed of the Ford at the moment of impact?