A couple is traveling by car down a straight high-way at 40 km/h. They see an accident in the distance, so the driver applies the brakes, and in 5.0 s the car uniformly slows down to rest.
(a) The direction of the acceleration vector is (1) in the same direction as, (2) opposite to, (3) at relative to the velocity vector. Why?
(b) By how much must the velocity change each second from the start of braking to the car’s complete stop?