What term describes linear movement in mechanics?

Translational motion refers to the movement of an object in a straight line from one point to another, which is characterized by changes in the position of the object over time. In mechanics, this type of motion is specifically concerned with the linear displacement of the object, meaning that all parts of the object move the same distance in the same direction.

Translational motion can be uniform, where the object moves at a constant speed, or non-uniform, where the speed varies. This concept is fundamental to understanding various principles in physics, including Newton's laws of motion, which describe how forces affect the movement of objects in a straight line.

In contrast to translational motion, the other terms mentioned refer to different types of motion: rotational motion involves the circular movement around an axis; periodic motion refers to any motion that repeats after a certain period of time; and circular motion specifically pertains to movement around a circular path. Thus, translational motion is the most accurate term for describing linear movement in mechanics.