Question

You' will find that motion problems and other physics problems often have several variables and other pieces of information to keep track of. The best way to tackle such problems is to draw a pictorial representation of the problem that shows all of the important details. The following Tactics Box explains how to draw a pictorial representation of a motion problem. In the following sketches a_z is the train's acceleration; t_i and t_f denote, respectively the time instants when the train starts to slow down and when it stops at the station; x_1, (v_z)_i, x_f and (v_z)_f are, respectively the train's position and speed at t_i and t_f. Which of the following sketches best represents the situation in this problem?

Answer 1

As shown from the diagram, the train initially accelerated and whose acceleration(ax) is in the direction of motion.

After a certain time interval, train stops slowly which means deceleration(opposite to the direction of acceleration(ax)).

Froom the figures given , figure 3 is the correct representation of motion of train.