What causes the sagging of electric wires?

Answer 1

in general gravity yes but engineers want this effect to take place and have taken countermeasures to eliminated its sideffects. it is a strain relief mechanism and gives tolerance to length changes due to temperature difference and movement due to earthquakes winds etc. the chang in temerature and gravity causes this but hte engineers couls elimintae this problem but they did not want it.

Answer 2

It's just nature of any wire or rope due to gravity.But electric wires for electric train are straight to make a constant contact with slider.It is done by another support wire to pull up the electric wire to be straight.

Answer 3

Sagging of electrical wires is caused by their own weight.

Answer 4

Electric transmission lines (and telecommunications and cable TV) are designed to 'sag' in order to reduce additional loading on the lines and the towers or poles that may be caused by wind, temperature changes, Ice, birds roosting and other factors (like the tower foundations moving a little, etc).

Answer 5

Expansion during summer from the heat. Heat causes the metals to expand. Most of them reverse the sag in winter.

Answer 6

Metals expand when they get heated. So, on sunny afternoons, the metal wire expands and sags due to the heat from the sun.

Answer 7

In a stiff material the bending moment is always at the middle. The same is with a wire hanging down.its maximum stretch is at the middle.

Answer 8

Elasticity

Answer 9

Curvature in spacetime.

Answer 10

gravity