This is because of the thermal expansion and contraction of the wires. Most materials expand when they are heated and contract when they are cooled. The amount of expansion or contraction is a function of the material's properties (specifically the coefficient of thermal expansion), the amount of heat supplied, etc. This means that some materials may expand (or contract) more as compared to others, for the same amount of heat supplied.
In summers, due to temperature increase, the wires expand. In comparison, the temperature decrease during winter will cause the wires to contract. If no slack was available during the summer and the wires were connected very tightly between any two sections, there would be no room for contraction in the winter season and the wires would break. To avoid that scenario, some slack is left in the wire to provide room for contraction.
Hope this helps.
No comments:
Post a Comment