text: The tension in the rope is providing the upward force causing the accelerating.\n\nFirst you need to find the net force acting on the object.\nNet force = mass * acceleration.\nYou are given the acceleration and mass, so this is easy to find.\n\nBut the rope does not just need to apply the net force, it must also apply enough additional force to counteract the objects weight.  The weight of the object,\nWeight = mass * gravity\n\nThe overall tension in the rope,\nTension = mg + ma\nor the weight of the car + the net force acting on the car.