A driver starting a car from rest accelerates uniformly to a speed of 30km/h in 2 minutes.

She maintains this speed for another 5 minutes then applies the brakes and decelerates uniformly to rest in 1 minute.

Now they ask to draw a velocity time graph, no axes given, just a sketch, which I did.

Then they ask calculate the acceleration in km/h^{2}for the first two minutes which I did and it is 900km/h^{2}

Then calculate the decelration in the last 2 minutes so it would be 0 -1800km/h^{2}= -1800km/h^{2 }

Now the part which is troubling me, they say calculate the total distance traveled in km. I know the area under the graph which is usually a trapezium is the total distance, however they just asked for a sketch, I don't really have any specific scales.

Their answer is 3(1/3)km but I'm not getting that.

I'm using this logic, for a period she traveled 5 minutes at 30km/h, so in 5 minutes the distance traveled would be 30km/h * 5/60 hours = 2.5 km.

Now I have to figure out the distance she traveled for the part where she accelerated and decelerated.. and yea I'm stuck.

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