A locomotive of mass starts from rest on a level track

PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials

Problem

A locomotive of mass

4.0\times10^{5}\,\text{kg}

starts from rest on a level track. It produces a constant horizontal tractive force of

1.2\times10^{6}\,\text{N}

over the first

200\,\text{m}

. Immediately afterwards, the tractive force falls to

6.0\times10^{5}\,\text{N}

and remains constant for the next

400\,\text{m}

. All retarding forces may be neglected. (i) Calculate the speed of the locomotive after covering the first

200\,\text{m}

. (ii) Determine its speed at the end of the subsequent

400\,\text{m}

. (iii) If the complete

600\,\text{m}

run described above takes

40\,\text{s}

, compute the average power developed by the locomotive during this interval.