Anatomy of Electrocution

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My dad is an electrician and he had a "no let go" shock when someone ignored the tag on the breaker and turned on the wires he was working on. He said he knew what was happening and kicked the ladder from under him which broke him from the wire and saved his life. Unfortunately the electricity damaged his heart and he has to take heart medication and routinely needs to get his heart checked for the rest of his life, but at least he's still alive!

This guy just explained resistance better than any physics teacher I've ever had

Correction: The term is Ventricular "Fibrillation" and not defibrillation. We doctors commonly call it as V. Fib. Fibrillation is similar to the word vibration or irregular contraction which is not a normal contraction of heart leading to it's normal physiology. Hence, "de-fibrillators" are machines used to stop the fibrillations or vibrations and contractions are induced through CPR.

Seeing all this scared the hell out of me, i'm truly shocked

My paternal granddad was an electrician. I remember him having us four grandchildren hold hands in tandem: Grandchild #1 would touch the radiator and grandchild #4 would hold Grandpa's hand. Then with his other hand, Grandpa would insert the 'blade' of his nail clippers into the "hot" (-) hole of the nearest receptacle/outlet so we could all feel the tingly current, until grandchild #1 (usually me) chickened out and let go of the radiator pipe, which would break the circuit and the tingling would stop. Fun times! until Mom found out and all the sudden we had a different baby sitter.

I almost died today from being electrocuted, 220v ac on a 2 Amp refrigeration compressor, I grounded a wire, and myself to the unit and got stuck there for about 3 seconds until I fell back off the ladder 1.5m to the floor.. I chilled for about 10 minutes and started feeling terrible, I could barely feel my heart beat and the muscles in my arms and hands totally contracted like I was having a seizure, I also felt like I was going into cardiac arrest so my work colleagues rushed me off to the hospital while giving me CPR, what a day.. I'm so happy to still be here, all I could think about is how much it would destroy my dad if I died, I think that's what saved me

It's worth mentioning that, despite changes in EM field spreading with the speed of light (including changes when an electrical circuit is connected), electrons themselves are moving relatively slowly, with a speed of about 0.5cm per second.

I’m a former Weapons & Electronics Engineer in the UK Armed Forces. I remember that in the first lesson in my training, my instructor said this, “Electricity isn’t dangerous, until you forget that it is”. This one phrase has stuck with me my whole life. Respect it, and you will be okay. Get complacent, and it will bite you in a heartbeat!! As the earlier version of my comment appears to have gained some criticism, I have edited it to remove the offending phrase!

Wow, so the entire central nervous system is shut down immediately after electricity is turned on in the electric chair. Meaning that the person receiving it cannot feel anything else but the initial shock. This also means that the first shock is to shut you down, the next is to toast your insides and the last one I have no clue why it would be applied... Maybe just to make sure you are dead by that point? Amazing... And terrifying...

As an Electrician I can say with confidence that electricity traveling from one hand across the heart to the other hand really hurts, you really feel your muscles tensing 50 times a second fortunately I have habits to avoid a death grip and have never been shocked for much more than a second

As an electrician, I have experienced "no let go". I had three fingers burned just like touching a hot frying pan. I was lucky enough to fall off of the contact. As an apprentice I had no business doing what it was I was doing. I am very safety conscious today. LOTO and proper PPE always.

At 12:25 there is a slight error. 60 Hz means 60 complete cycles per second. That is 60 positave and 60 Negative parts of the wave. Totalling the electricity starting and stopping 120 times per second.

A few nuances about electricity While the model of electrons moving in a straight line through the wire is useful, in reality they are moving in random directions with a relatively miniscule drift velocity caused by the electric field. Veritasium's video explains it well if you want to learn more: https://www.youtube.com/watch?v=oI_X2cMHNe0 "Rubber has a resistance of 10 -100 MOhms" Particular objects have a resistance, the way materials are measured is with resistivity. The formula for resistivity is: ρ = R(A/ℓ), resistivity equals resistance times cross-sectional area divided by length. The units of resistivity is simplified to Ohms*Meters but it is really Ohms per unit of Length per unit^2 of Cross-Sectional Area. For example, if an object had a cross-sectional area of 1 cm^2, a length of 1 cm, and a resistance of 100 ohms, that material would have a resistivity of R(A/ℓ) => 100(1/1) = 100 ohm-meters. An object of the same material with a cross-sectional area of 1 cm^2 and a length of 2 cm would have a resistance of ρ/(A/ℓ) => 100/(1/2) = 200 ohms. "When electricity passes through your skin, the high amount of resistance generates heat" For an ideal voltage source, higher resistance actually means there is less power P = V^2/R. Hence why electrical workers wear rubber gloves. However in real life, voltage sources have a source resistance so as the load resistance becomes smaller, the power will peak then get smaller(https://en.wikipedia.org/wiki/Maximum_power_transfer_theorem ). Adding the sponge to the prisoner's head decreases the resistance and actually results in a greater power transfer. The reason the sponge stops burns is because water has a high specific heat capacity and will reach a lower temperature than bare skin despite absorbing more energy. "This means the current would be turning on and off 60 times per second" It would be 120 times per second. In the flickering lightbulb, the times when it is on are the peaks and troughs of the sine wave, when electrons are moving fastest in either direction. The times when it is off are the inflection points, when the electrons are still.

My Dad is a handyman by trade and a consummate do it yourselfer, but he never messed with electricity. He’d fix most anything in the house, but when we had electrical issues, he always hired a professional.

Higher frequency AC is less likely to be lethal than DC or lower frequency AC, because of the skin effect. This tends to make current to flow more along the surface of a conductor than in its interior (because in the interior, the changing magnetic field induces reverse voltage that causes electrons to repel one another). This is why a Tesla coil doesn’t kill; most of the current stays on the skin increasing the resistance and reducing current. Inductors used to tune the frequency at which a high powered radio transmitter operates are often hollow pipes to save weight and cost, since the current only flows on the surface.

Dude explained it better than any teacher I ever had lmao. I really like the water analogy.

Muscle contraction due electricity is something my dad taught me when I was 4. He taught me to (only if there is no other way) to check surface of potentially electrified object with outer side of palm or finger.

Another reason lower AC voltages are fatal is because the peak voltage is considerably higher than the RMS voltage, which is the figure used to convey the average amount of work done by a voltage that is always changing.

These are really informative and interesting. Your channel deserves more recognition