You are driving along the road in a rented moving van that has a mass of 4000 kg. You have just slowed down to 7 m/s (about 15 mph) because you're in a school zone. It's a good thing you thought to do that because a group of first graders are just starting to cross the road. Just as you pass the children you see a 1000 kg sports car in the oncoming lane heading straight for the children at 40 m/s (about 90 mph). Oh no! A desperate thought crosses your mind: you have just enough time to swing into the oncoming lane and speed up a bit before making a head-on collision with the sports car! Assuming that the collision is inelastic, how fast do you need to go to stop the sports car?
