**An 8000 kg engine pulls a train of 5 wagons, each of 2000 kg, along a horizontal track. If the engine exerts a force of 40000 N and the track offers a friction force of 5000 N, then calculate:**

**(a)** the net accelerating force and

**(b)** the acceleration of the train

Asked by Vishal kumar | 1 year ago | 256

**(a)** Given, force exerted by the train (F) = 40,000 N

Force of friction = -5000 N (the negative sign indicates that the force is applied in the opposite direction)

Therefore, the net accelerating force = sum of all forces = 40,000 N + (-5000 N) = 35,000 N

**(b)** Total mass of the train = mass of engine + mass of each wagon = 8000 kg + 5 × 2000 kg

The total mass of the train is 18000 kg.

As per the second law of motion, F = ma (or: a = F/m)

Therefore, acceleration of the train = (net accelerating force) / (total mass of the train) = 35,000/18,000 = 1.94 ms^{-2}

The acceleration of the train is 1.94 m.s^{-2 .}

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Time (seconds) |
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0 | 0 |

1 | 1 |

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4 | 84 |

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6 | 216 |

7 | 343 |

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