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**djmccabie** A miniature train runs on a track, which has a straight horizontal section AB. The power of the train's engine t seconds after passing the point A is given by (3 + 8t - 3/5t²)kW. The time taken to travel from A to B is 5s.

a) show work done by the engine between A and B is 90 000J.

in kJ, $\displaystyle \textcolor{red}{W = \int_0^5 3 + 8t - \frac{3t^2}{5} \, dt}$

b) The total mass of the train and its load is 1000kg, and the speed of the train at A is 4 m/s. Given that the work done against resistances between A and B is 13500J, calculate the speed of the train at the point B.

**strike error ...**