Relative motion in one dimension involves understanding how the motion of an object is perceived from different reference points, particularly when one of those points is also in motion. The acceleration equation can be derived by analyzing the differences in velocity between a stationary observer and a moving object. This concept highlights the distinction between absolute motion and relative motion, emphasizing that motion is always measured in relation to a chosen reference frame. The discussion encourages a deeper exploration of how these principles apply in practical scenarios. Understanding relative motion is crucial for solving problems in physics effectively.