1500kg car pulls a 600kg trailer away from the stoplight with an acceleration of 2.0m/s^2. Questions below

Question

On vacation, your 1500kg car pulls a 600kg trailer away from the stoplight with an acceleration of 2.0m/s^2, What is the net force exerted on the trailer, what force does the trailer exert on the car, and what is the net force acting on the car?

Answer 1

Net force exerted on the car is m*a = 1500kg * 2m/s^2 = 3000 N

Net force exerted on the trailer is        m*a = 600kg * 2 m/s^2 = 1200N 

To determine the net force exerted by the trailer on the car, we note that all of the force acting on the trailer is exerted by the car.  The forces exerted by the trailer by the car is equal and opposite to the force exerted by the car on the trailer.  Magnitude = 1200N.