A train passes through station A travelling at 10 ms

-1

along a straight track.

For the first 5 seconds after leaving the station the train has a constant acceleration of

7 ms

-2

.

The train then travels with constant velocity for a time, T, until it decelerates uniformly

for 15 seconds, coming to rest at the station B which is 2.68 km away from A.

Sketch a velocity time graph for the motion of the train and calculate the time taken to get

between the two stations