Method of perceived electric shock?

[newfutile]

If we assume our feet are insulated from the ground why do we get a tingle if touching a live wire?

 

[LastManOnline]

If we assume our feet are insulated from the ground why do we get a tingle if touching a live wire?

Because the overall resistance of the path through our bodies, socks, shoes and the ground beneath our feet is allowing sufficient current to flow to be felt. When working on anything live I never assume my feet are insulated. I always grab a wooden pallet or suchlike as extra "insurance"

 

[Lucien Nunes]

Also because of stray capacitance. A small AC current can pass from your body to earth via the capacitance between your entire surface area and the surface area of all earthy things around you. At 230V 50Hz this can sometimes be enough to feel, and will increase proportionally with voltage and frequency. Obviously does not occur with DC.

 

[newfutile]

I would not think there is any direct current path especially if in an upstairs room with carpet floor boards and thick rubber on boots shoes, then again there cant be much capacitance.
i seem to remember in the days of neon screwdrivers they would light brighter in some locations ,like a concrete garage floor .

 

[LastManOnline]

I would not think there is any direct current path especially if in an upstairs room with carpet floor boards and thick rubber on boots shoes, then again there cant be much capacitance.
i seem to remember in the days of neon screwdrivers they would light brighter in some locations ,like a concrete garage floor .

Correct. Although there are no perfect insulators. There is always current flow. Ohms law determines how much

 

[Lucien Nunes]

there cant be much capacitance.

It's a few hundred pF, giving an Xc on the order of 10MΩ and currents of a few tens of μA. Not enough to shock, but detectable under certain conditions.

Although there are no perfect insulators. There is always current flow

Standing on a good insulator, the capacitive current will dominate even at 50Hz, followed by the surface leakage, followed by the current passing through the bulk resistance of the insulator. So while this statement is true, a good insulator is the least significant contributor and the bulk current lost amongst the noise in the situation described.

Of all measurable parameters of everyday objects, resistivity is the most wide-ranging. PET (the plastic that drinks bottles are made of) has a resistivity of 1x10^21Ωm compared to 1.7x10^-8Ωm for copper. I.e. the ratio of resistance of two identically sized specimens of the two materials is around 60,000,000,000,000,000,000,000,000,000.

 

[littlespark]

Don’t work on it live. ?

 

[static zap]

, but detectable under certain conditions.

Touching lightly-for a small area of contact , or on a hangnail injury in sensitive delicate skin near a finger tip/beside a nail.
( Gripping bare metal tight -may reduce tingle -BUT can be FATAL ,
if current is not restricted ) .. bad habits from a "game".