Uniform rectilinear motion The movement is relative The movement of a body, seen by an observer, depends on the reference frame in which the observer is situated. Source: https://th.bing.com/th/id/R.e77fbd76f41c851355c4417b3653c06e?rik=kb076FHHKTn9uQ&riu=http%3a%2f%2fprofademir.no.comunidades.net%2fimagens%2ftraj.gif&ehk=cz0F%2bfhrQcrCGDUQKSOFBZOfiEy%2fpSqtN6v6UbV8%2b7g%3d&risl=&pid=ImgRaw&r=0 An observer B, in a train (which moves on the tracks), and the observer A, stationary on the Earth. For observer A, observer B is in motion, along with the train. However, from the point of view of observer B, observer A is moving in the opposite direction to the movement of the train on Earth. Uniform rectilinear motion Distance, speed and time When a body moves with constant velocity along a rectilinear path, we say that its motion is uniform rectilinear. The word "uniform" indicates that the velocity value remains constant. We can find the distance traveled by an ...