According to Newton's second law, the acceleration of an object is directly proportional to the net force acting on the object, and inversely proportional to the mass of the object. In this case, the net force acting on the parked car is greater than the net force acting on the dump truck. This is because the dump truck has a much greater mass than the parked car, so the same amount of force will produce a smaller acceleration in the dump truck.
Therefore, the parked car experiences greater acceleration.
