Electric shock occurs upon contact of a (human) body part with any source of electricity that causes a sufficient current through the skin, muscles, or hair. Typically, the expression is used to describe an injurious exposure to electricity.
The minimum current a human can feel depends on the current type (AC or DC) and frequency. A person can feel at least 1 mA (rms) of AC at 60 Hz, while at least 5 mA for DC. The current may, if it is high enough, cause tissue damage or fibrillation which leads to cardiac arrest. 60 mA of AC (rms, 60 Hz) or 300–500 mA of DC can cause fibrillation. A sustained electric shock from AC at 120 V, 60 Hz is an especially dangerous source of ventricular fibrillation because it usually exceeds the let-go threshold, while not delivering enough initial energy to propel the person away from the source. However, the potential seriousness of the shock depends on paths through the body that the currents take. Death caused by an electric shock is called electrocution.
If the voltage is less than 200 V, then the human skin, more precisely the stratum corneum, is the main contributor to the impedance of the body in the case of a macroshock—the passing of current between two contact points on the skin. The characteristics of the skin are non-linear however. If the voltage is above 450–600 V, then dielectric breakdown of the skin occurs. The protection offered by the skin is lowered by perspiration, and this is accelerated if electricity causes muscles to contract above the let-go threshold for a sustained period of time.
If an electrical circuit is established by electrodes introduced in the body, bypassing the skin, then the potential for lethality is much higher if a circuit through the heart is established. This is known as a microshock. Currents of only 10 µA can be sufficient to cause fibrillation in this case. This is a concern in modern hospital settings when the patient is connected to multiple devices.
... Electronic training involves the use of an electric shock as an aversive ... remotely, or that are triggered by barking, fencing that delivers a shock when a dog wearing a special collar crosses a buried wire, and mats that can be ... The use of electric shock aversives for training dogs is the subject of considerable controversy ...
... The Leiden accumulator, created in 1745 was the first device that produced electric shock for medical purposes ... and a community of monks, all holding onto a chain, and given an electric shock which made them fall "like a set of dominoes" ... Electric shock therapy was supposed to cure paralysis, gout, haemorrhoids, epilepsy ...
... Electric shock delivered by an electric chair is sometimes used as an official means of capital punishment in the United States, although its use has become rare ... Although some original proponents of the electric chair considered it to be a more humane execution method than hanging, shooting, poison gassing, etc ... Modern reporting has claimed that it sometimes takes several shocks to be lethal, and that the condemned person may actually catch fire before the process is complete ...
... One was the electric bath, which consisted of sitting the patient on an insulated stool with glass legs and connecting the patient to one electrode ... treatment could be performed while the patient was in the electric bath ... The third class of treatment was electric shock therapy, in which an electric shock was delivered from a galvanic battery (later electromagnetic generators ...
Famous quotes containing the words shock and/or electric:
“a fortress against ideas and against the
Shuddering insidious shock of the theory-vendors
The little sardine men crammed in a monster toy
Who tilt their aggregate beast against our crumbling Troy.”
—Louis MacNeice (19071963)
“The sight of a planet through a telescope is worth all the course on astronomy; the shock of the electric spark in the elbow, outvalues all the theories; the taste of the nitrous oxide, the firing of an artificial volcano, are better than volumes of chemistry.”
—Ralph Waldo Emerson (18031882)