78. The Walking Passenger. The train is moving at a speed of 60 km/h. A passenger is walking from the end of the train to its beginning through the passageways between the cars at a speed of 3 km/h. What is the speed of the passenger relative to the railway track?

We are not going to engage in sophistry here, like Zeno's paradox of the flying arrow, or Einstein's theory of relativity, but are talking about movement in the ordinary sense of the word relative to the railway track.
78. Suppose a train travels for an hour and has an incredible length of 3 km. Then (see figure) in this time it will travel from \(B\) to \(C\) 60 km, while the passenger will move from \(A\) to \(C\), or 63 km. C

![](https://cdn.mathpix.com/cropped/2024_05_21_56f37ca27ac3d928838dg-201.jpg?height=271&width=834&top_left_y=1298&top_left_x=611)

On the other hand, if the passenger walked from the locomotive to the end of the train, the train would have traveled the distance from \(B\) to \(C\) (again 60 km), while the passenger would have moved only the distance from \(B\) to \(D\), that is, 57 km. Therefore, in the first case, the passenger's speed relative to the railway track is 63, and in the second case, \(-57 \mathrm{km} /\) h \(^{*}\).