A car is approaching an intersection and is 17.5 m away. The driver notices that the light turned yellow and accelerates the car with a constant acceleration. One second later the car passes through the intersection and (according to the photo-radar) is moving at 20 m/s.
(a) What is the acceleration of the car? (Express direction in terms of the direction of motion of the car)
(b) What is the initial speed of the car?
(c) Justify the direction of the acceleration in light of the motion of the car and the answer to (b).