Answer to Question #106166 in Classical Mechanics for Durry

Question

2 trains trains x &y travel on 2 parallel tracks in same directions with uniform accelerations 15 & 10m/s,pass a railway station at same instance.Speeds of x &y at that moment 72km/h, 108km/h respectively.After some time x passed y at a place.
A)Draw the v-t graph for both x &y in same axis.
B)Determine the time which is taken by x to pass y using that graph

Answer 1

a) The graph is here. It's plotted for both trains according to the basic equation for speed over time during accelerated motion:

$$v(t)=v_0+at.$$

b) According to the graph, at a time before 2 seconds train y was moving faster than x. At 2 seconds they both had the same speeds. After 2 seconds train x overtook train y .