College Physics with MasteringPhysics 7th Edition by Jerry Wilson,Anthony Buffa,Bo Lou

Exercise 56

An observer by the side of a straight, level, north- south road watches a car (A) moving south at a rate of 75 km/h. A driver in another car (B) going north at 50 km/h also observes car A. (a) What is car A's velocity as observed from car B (Take north to be positive.) (b) If the roadside observer sees car A brake to a stop in 6.0 s, what constant acceleration would be measured (c) What constant acceleration would the driver in car B measure for the braking car A