Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.

I have observed that the power lines buzz louder when there is less moisture in the air.

Why is this?

If it will help the lines are located on the foot hills of a nearby mountain.

share|improve this question
1  
have a look at physics.stackexchange.com/a/45488/4020 –  Yrogirg Dec 13 '12 at 9:04
    
Thanks @Yrogirg! –  Velox Dec 13 '12 at 14:31

2 Answers 2

In 1999, the president of the IEEE Power Engineering Society, Robert Dent, noted that:

"The degree or intensity of the corona discharge and the resulting audible noise are affected by the condition of the air--that is, by humidity, air density, wind and water in the form of rain, drizzle and fog. Water increases the conductivity of the air and so increases the intensity of the discharge [..] corona discharges can be produced by water droplets, fog and snow.". (Ref)

share|improve this answer

The speed of sound is only about 0.1% - 0.6% faster in dry air than in humid air at the same pressure and temperature, but humid air is also less dense than dry air, so my best guess is that the vibration from the wires couples less strongly to air that has moisture in it than it does to denser dry air.

share|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.