A locomotive of mass pulls five identical railcars

PHYSICS · Single correct · A Level · Physics · Mechanics and materials · Mechanics and materials

Problem

A locomotive of mass

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

pulls five identical railcars, each of mass

4.0\times10^{4}\,\text{kg}

. The locomotive’s drive wheels exert a forward force of

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

on the track. Rolling resistance of

1.0\times10^{4}\,\text{N}

acts on each railcar, while resistance on the locomotive is negligible. What is the magnitude of the train’s acceleration? (a)

0.30\;\text{m/s}^2

(b)

0.18\;\text{m/s}^2

(c)

0.15\;\text{m/s}^2

(d)

0.43\;\text{m/s}^2