Q. A light train is travelling on a straight section of track at a constant speed of 15 rm m/s. As it approaches next station, it starts to slow down at a rate of 5 rm m/s^2 until it stops at the station. From the moment the train starts to slow down, how long does it take for train to reach the station? Suppose that the train is moving toward the right and starts to slow down at t = 0. The separation of each dot represents an elapsed time of one second. Include velocity vectors and the acceleration vector. Keep in mind that the acceleration of train has a magnitude of 5 {rm m/s^2}. What are the known and unknown factors?