Based on the Newton's laws of motion, the motion of an object is due to an unbalanced net force.
<h3>What is Force?</h3>
A force is a push or pull effect which causes a change in the motion or state of an object.
Newton's second law states that the acceleration of an object is to the net force acting upon the object, and inversely upon the mass of the object.
Thus, motion occurs when there is greater net force acting on an object.
From the diagram shown above, when a force of 3000 N is applied by the man, the boxcar does not move because the force applied by the man is less than the force on the boxcar.
The box car will move if a force greater than that on the boxcar were applied to it.
According to Newton's third law of motion, for every force, there is an equal but oppositely acting reactionary force, therefore, the net force on the boxcar is 0 N.
Therefore, the motion of an object is due to an unbalanced net force.
Learn more about net force at: brainly.com/question/14361879