For what reason should the tram driver slow down when driving through a place with lowered overhead line e.g. under a viaduct?
Show the correct answer
Correct answer
B. Because quick passage through such a place may damage the current collector and traction.
Explanation
This question is about a tram passing through a place where the overhead contact line is lowered, for example under a flyover (viaduct). The tram driver should slow down because passing through quickly may damage the current collector and the overhead line (traction) - the answer is B.
Where the overhead contact line is lowered, the contact wire changes height, and the pantograph has to go down and rise again over a short section. At high speed, the current collector hits the wire and may bounce off it, spark, damage the contact strip or even tear down the overhead line. That is why the tram driver drives slowly under a viaduct. An echo (answer A) is not a reason to reduce speed, and a lowered overhead line does not affect how well the brakes work (answer C). A torn-down overhead line would stop tram traffic for a long time.
Legal basis: Art. 3 para. 1 and Art. 19 para. 1 of the Road Traffic Act (Prawo o ruchu drogowym)