This is how railway power lines work despite thermal expansion and contraction
When traveling using trains, it is common to notice hanging weights near the poles. This is perplexing as power can travel through a simple transmission line, one that you would assume railway engineers would develop.
In this video, YouTuber Lesics uses his usual style of imaginatively illustrating science and engineering principles to tackle this question: why are railway power lines so complex?
The answer is a surprisingly simple one, and it has to do with thermal expansion and contraction. The first is a process that happens to railway wires over the summer.
They expand, causing the wires to hang down. This is very dangerous as they can go low enough to actually hit the traveling train. In the winter, thermal contraction causes the wires to shorten and possibly break.
To protect against both these incidents occurring, engineers have come up with an innovative solution that includes the weights placed near the railway poles.
How does this solution work? What is the science and engineering behind train travel? Is this really the safest alternative? Don't railway lines experience thermal expansion and contraction regardless? What is the future of train travel? This video answers all these questions and more.
With many scientists still unhappy with the IAU's definition of "planet," it's possible the debate will never be resolved!