The vertical forces present in a boxcars being pulled by a train are weight and pull of air on the boxcars.
The forces exerted on an object can be resolved into <em>horizontal</em> and <em>vertical components.</em>
<em />
The horizontal components of the forces on an object being pulled include the following;
- The frictional force on the object; which tends to reduce the motion,
- force dragging the object forward
- if the object is inclined to an angle, the horizontal component of the weight
This horizontal force is written as;

The vertical component of the force on the object include the following;
- the weight of the object acting downwards
- the pull of air on the object acting upwards
The vertical force on the object is written as;

Thus, the vertical forces present in a boxcars being pulled by a train are weight and pull of air on the boxcars.
Learn more here: brainly.com/question/2000189