A driver is driving once again from Nogales to Tucson on I-19, past the wreck of the car that veered off the road and struck a cactus, surrounded by a throng of industrious physics students measuring the skid marks, the crumpled hood, and the indentation on the driver's forehead. Abruptly a roadrunner darts out into the middle of the road. It doesn't see her at first, because it is focused on a tasty lizard it's trying to catch. She slams on her brakes, and the sound of squealing brakes alerts the bird to the onrushing car; it tries to hop out of the way.
Hint: You will require the quadratic formula for this problem.
1. If she is initially traveling at 110 km/hour, the roadrunner is 30m in front of her when she applies her brakes, and the brakes decelerate the car at 9 m/s^2, how long does the bird have to dodge the car?
2. Graph the position vs. time of the car, and label the position of the roadrunner on the graph.
3. The quadratic formula gives you two solutions to the quadratic. Which one is the physically meaningful answer? What does the other solution mean?