Answer:
Before collision: newton's first law - since uniform motion
On collision : newton's second law - since change in momentum
Explanation:
Newton's first law states it is the inertia of the body to remain in a state of rest or in a uniform motion in straight line unless acted upon by an external force. Since, the car is under uniform speed
Newton's second law states that the force acting on a body is directly proportional to the change in momentum. Since the momentum of car changes in short interval of time.
Hence, the forces acting on the car can be explained with the help of newton's first law and newton's second law.