Why does Static cling happen in warm weather?

[Math Is Hard]

I've been dealing with lots of static cling over the last week. I always thought this phenomenon had something to do with the cold air of winter - but it has been 75 to 85 degrees F here all week.

What gives?

 

[mgb_phys]

Emily Post advises don't wear cling film before valentine's day!

 

[Math Is Hard]

Well, I'm foregoing the clingy dresses, but my hair is a mess (looks something like the picture below). Is it the dryness of the air that matters?

 

[mgb_phys]

Yes - conductivity depends strongly on humidity.
Of course not hanging onto high voltage supplies is also important

 

[Math Is Hard]

We have "Santa Ana conditions" here which give us blasts of warm, dry air. We get these now and then and they happen in Fall, Winter, and sometimes Spring.
http://en.wikipedia.org/wiki/Santa_Ana_winds

The funny thing is - in the other seasons when we have Santa Anas, I don't notice static cling in my hair or getting shocked touching doorknobs. It might just be my own bias. Maybe I'm not expecting it -- so maybe it happens but I don't just notice it.

 

[turbo]

Lovely hair, MIH! Static electricity effects happen easily in really dry conditions even if it is not cold out. In northern climates, it is common to get dry conditions as a function of low temps, but that (low temp) is not a precondition. I have been in some industrial environments when I was "snapping and popping" with static shocks even though it was VERY warm. Sometimes, this was happening in the basements of late-stage dryer sections on paper machines - the movement of the dryer felts around the steam-heated steel dryer drums produced effects similar to those of a Van de Graaf generator.

 

[physics girl phd]

Humidity does effect the likelihood of static electricity (since high humidity levels help charge transfer back to equilibrium distributions (or at least closer to it). In Colorado, when the cat got static shocks when I was petting her, I would humidify my house by boiling a big pot of water on the stove.

 

[Gokul43201]

We get these now and then and they happen in Fall, Winter, and sometimes Spring.
http://en.wikipedia.org/wiki/Santa_Ana_winds

The funny thing is - in the other seasons when we have Santa Anas, I don't notice static cling in my hair or getting shocked touching doorknobs.

That seems plausible.

What is most important to the rate at which you dissipate static charge to the air is the moisture content in the air, which is better quantified by the dew point rather than the relative humidity (RH). At higher temperatures, the air has a greater capacity to hold moisture, so that an RH of 20% describes drier air when the temperature is 70F than when it is 80F (Spring/Fall).

There's also an independent contribution from temperature to the dissipation rate (which scales with the absolute temperature, in K) but that is likely too weak to make any noticeable difference.

 

[Math Is Hard]

I have been in some industrial environments when I was "snapping and popping" ...

You were breakdancing? Oh, wait, maybe that's "popping and locking". I get mixed up.

Humidity does effect the likelihood of static electricity (since high humidity levels help charge transfer back to equilibrium distributions (or at least closer to it). In Colorado, when the cat got static shocks when I was petting her, I would humidify my house by boiling a big pot of water on the stove.

hmm... I am going to try that. My cat IS getting peeved about the static. Maybe I could try running hot shower water, too.

At higher temperatures, the air has a greater capacity to hold moisture, so that an RH of 20% describes drier air when the temperature is 70F than when it is 80F (Spring/Fall).

Thanks, Gokul. I didn't know that.

 

[Greg Bernhardt]

I keep my place between 38-40 humidity and I still get quite a bit of static.

 

[hypatia]

If you rub your comb and brush on a dryer sheet, then use it on your hair, it helps. But on the down side, you smell like the dryer sheet.

 

[turbo]

Between the wood stove and the arctic air masses of winter, I rarely see more than 20% RH. Take off a fleece pull-over, and SNAP!

 

[Evo]

I have a terrible problem with static when I try to open any of the freezer doors at the grocery store. I don't notice this happening to anyone else. It's so bad that I quickly hit the door handle with my thumb to disperse the static so that it's just the tip of my thumb that gets shocked instead of my whole hand. People that see me cringing and slapping the door handle must think I am nuts.

 

[Kurdt]

Can't remember the last time I had a static shock.

 

[Math Is Hard]

*shocks Kurdt*

wahahHAHAHhhaahaha!

 

[Kurdt]

*shocks Kurdt*

wahahHAHAHhhaahaha!

Naked women don't shock me any more

 

[wolram]

Shocks do not bother me much, i helped build a candy bar wrapping machine, the wrapping starts of on big spool, the foil is fed up and over rollers then under a former, when that thing got up to speed no one wanted to get near it, i used to have a good laugh when newbies were shown it, and was even given a new nickname.

 

[hypatia]

Maybe you all should tie a chain to your back side, and let it drag behind you. I've seen people do that with autos.

 

[Evo]

Maybe you all should tie a chain to your back side, and let it drag behind you. I've seen people do that with autos.

Ahahaha, not a bad idea.

 

[turbo]

In 1982, when we were starting up a new paper machine, the paper was often over-dried. After the paper was wound onto large reels, the reels were kicked down a pair of rails to the winders, and the winder operators would thread the sheet up and over some rubber/composition rolls, through a set of rotary slitters, and then alternately either to winding stations on the front and back of the winder. On days when it was dry, and the sheet was dry, the static shocks could be impressive - fat blue sparks. One of the new helpers on the winder was complaining about all the shocks, and the lead winder operator (a real practical joker) told him that he could cut down on the shocks by grounding his shoes, so that night the guy stopped at the hardware store and bought a box of brass tacks, and hammered brass tacks into the bottom of the soles around the edges. The next day, he was getting shocked more frequently and more painfully than ever. The other guys on the crew were calling him "lightning", "sparky", and other names, and asked if they could borrow his "magic boots".

 

[Andre]

I have a terrible problem with static when I try to open any of the freezer doors at the grocery store. I don't notice this happening to anyone else. It's so bad that I quickly hit the door handle with my thumb to disperse the static so that it's just the tip of my thumb that gets shocked instead of my whole hand. People that see me cringing and slapping the door handle must think I am nuts.

Use a key, tough metal things with a key first and the discharge will be much less noticeable. No key around? turn around and tough the door knobs with the back first.

 

[glueball8]

Walking outside with big coat on plus listening to MP3 is not a good idea.

 

[Math Is Hard]

I found out last night that I make a pretty good night light.

 

[physics girl phd]

Maybe you can start wearing an http://people.csail.mit.edu/rahimi/helmet/" .
Several design options are available. The centurion is particularly attractive:

http://people.csail.mit.edu/rahimi/helmet/centurion.JPG

 

[wolram]

I found out last night that I make a pretty good night light.

MIH night lights just charge and go no power cords or batteries, $29 99.

 

[Evo]

I found out last night that I make a pretty good night light.

Do tell.

I am reminded of an episode of Friends where Russ had his teeth whitened and they glowed under a black light.

 

[Math Is Hard]

well, it wasn't my teeth making me light up, it was the sparks. Every time I would turn over I'd make a shower of sparkles from moving the sheets around. sssSShhipppp-p-p!

I had one of those foil hats, physics girl. But it went missing one day. I think the people from the government found out about it and broke in my house and took it.

 

[turbo]

well, it wasn't my teeth making me light up, it was the sparks. Every time I would turn over I'd make a shower of sparkles from moving the sheets around. sssSShhipppp-p-p!

I think we should set up a lab, feed you lots of coffee (so you don't sleep soundly) and see how much electricity we can get out of the Texas Twister.

I do love Little Feat!

 

[Evo]

Electric Humans

Hmmmm, tonight on Discovery Health Channel - Electric Humans

Humans aren't generally known to be conductors of electricity but in this fascinating documentary through a series of tests, we explore the amazing feats a few electric humans who can light cigarettes with their hands and turn lights off with their minds.

 

[Math Is Hard]

Hmmmm, tonight on Discovery Health Channel - Electric Humans

My friends at the soap shop will be watching that one!