A 132 meter long train passes an electric pole in 6 seconds. The speed of a train is?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → 79.2 km/h
A pole has no length worth counting, so the train has passed it when its whole length has gone by: the distance covered is only the train’s own length. Speed is that distance divided by the time; to change metres per second into kilometres per hour, multiply by \(\frac{18}{5}\) (1 m/s is 3,600 m in an hour, that is 3.6 km/h).
Speed in m/s: \(132\div6=22\)
Speed in km/h: \(\displaystyle 22\times\frac{18}{5}=79.2\)