Questions tagged [static]

Anything related to static electricity, i.e. the physical phenomenon in which electric charges accumulates on objects even in absence of a steady current flow. Do NOT use for questions about electronics in a state of equilibrium (i.e. as opposed to transient or dynamic behavior).

Anything related to static electricity, i.e. the physical phenomenon in which electric charges accumulates on objects even in absence of a steady current flow.

See also Wikipedia on static electricity.

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Measuring feline capacitance

When I pet my cat, and then touch her on the nose, I get a little shock. Sometimes, when she walks up to something, her nose sparks and she jumps back and puffs out. I was wondering how I might go about measuring the capacitance of my cat. So how…
timthelion
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Anti-static bags - safe to support powered circuit boards?

Is it generally safe to rest a low voltage powered up circuit board on an anti-static bag when debugging? A simple meter reading suggests it is a good insulator, but it must conduct to some extent? Ditto on anti-static mat on the workbench
Dirk Bruere
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Static shocks all over the building

I just came from the local library, it’s quite big, and most of it is made of an architectural design using mostly painted metal book shelves painted with some kind of anticorrosive paint along with glass floor all over the place, everything was…
GoatZero
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Does changing the gap between plates change the capacitor voltage?

Consider an ideal capacitor which has a length of \$\ell_1\$ between its plates. The capacitor terminals are open; they are not connected to any finite valued impedance. Its capacity is \$C_1\$ and it has an initial voltage of \$V_1\$. What happens…
hkBattousai
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How does static dissipative foam work?

I am planning to build a grip-release sensor using the foam. I'm pretty interested in the way it works. Does the resistance in circuit increase or decrease when force is applied onto it? And this will be proportional to the force in what manner? I…
Karl Stark
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How often does static kill computer components? In the past? Now? What's the difference?

Full disclosure: I'm a computer engineer and a software dev. I'm not an electronic engineer. If this question has already been answered, please link to it, I've done cursory searches on Google and SE and not got anywhere. Please don't flame me. Back…
Skrrp
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Why does a sweaty finger neutralise the touch-sensor on my phone screen?

My experience is that when I'm running, my fingers "don't work" on my phone screen. My understanding was that the sensor on a touch screen works on static-charge, ie that you act as an 'earth' to the screen and it can sense the difference in charge.…
hawkeye
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What is the smallest metal object you can ground yourself with?

Say I am installing a new CPU in my desktop motherboard and I am interested in grounding myself (by touch or one of those nifty bracelets) to avoid damaging my components. What is the nature of grounding? Does grounding effectiveness correlated to…
Dent7777
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What is the purpose of input protection on USB (or at all)?

I have seen quite a bit where reverse biased diodes are used to clamp input voltages when spikes occur. What is the typical reverse breakdown voltage for a diode used in this type of application? It appears that these protection diodes are in place…
sherrellbc
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Getting rid of static charge in fuel tanks

Back in the olden days, fuel trucks had a chain suspended from the axle to the ground to dissipate the explosive static charging fuel will buildup from sloshing around inside a tanker. I remember them being banned, but what replaced the chains?
Gary Anders
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Avoiding static shocks from vehicles

I don't entirely understand static electricity; particularly how it seems to flow through rubber shoes and paint, but seemingly not rubber tyres or car seats. I am tired of getting shocks from my van. I've read that those anti-static strips for…
Jayy
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Can air itself be theoretically considered as a (very poor) wireless ESD grounding strap?

There are many kinds of questionable ESD wriststraps available which claim to provide ESD protection "wirelessly". When asked about how exactly they work, they cite dubious claims about physics as their theory of operation. Many experiments have…
比尔盖子
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How do arcs generate radio-frequency

When I have an electric arc, and put an AM radio nearby, I hear a crackle and the station that I previously heard goes away. I am wondering what is going on with the electricity through the air to generate the noise that I heard through the radio.
skyler
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What keeps frying my RF switches?

Short version: What might be breaking the first sensitive component connected to an ungrounded 14cm UHF dipole antenna mounted 30' above the ground? Could it be related to static electricity? I have designed a built a few simple weather stations…
Barry Smith
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Measuring absolute static charge

A old way of measuring static charge is using a gold leaf electroscope. image by User:Stw on wikipedia If I understand things correctly, this instrument requires no ground and measures what I'm going to call "absolute" charge. This is in contrast to…
Anamne
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