b)Why does an electric shock to the hand cause the first to clench the wire firmly?
539923
Flex your hand both ways. Which way seems the strongest: the opening of your hand or the closing? The closing, of course. Our hands are made to hold onto things, just like babies grab onto fingers presented to them, just like little monkeys grip their mothers.\n\nWhen we are shocked, the electricity causes all muscles to contract, the ones that cause our hands to open and the ones to close. Which ones are bigger and more powerful? The onese to close. Those win out and so we grip the wire.\n\nThat is why if you want to test to see if a circuit is hot and you insist on touching it with your bare hand, use the back of your hand not your palm. The reflex will pull you away from the wire.
259472
ELECTRICAL IMPULSES sent down by "nodes" thru conducting pathways towards the atria and ventricles.......these atria and vents r made of muscles which contract on recievin the electrical shocks........and thats when the blood moves forward\nwhen their is no impulse being sent forward........the chambers of the heart relax and get filled with blood.....\n\njust waiting for the next impulse to come by and the heart contracts again\n\nthis goes on n on till u die!
1119885
Ok... I read the answers previously posted and they all sound reasonable close to the truth, so I'll leave them be.. they did fail to mention how a person is actually killed by a lightning strike... So I'll answer this for you...\nYour body uses the flow of charged ions to control many processes (i.e. Muscle movement, nerve signalling).  The flow of charge is more commonly known as electricity.  The average membrane potential in a human is -70 kilojoules(kJ), and the channels in your cells membrane can be triggered by an impulse of only about 20 kJ.  So when you get a current through your body with a potenial of thousands of volts... obviously there is going to be a disruption of the charge gradient.  Depending on the path of the current through the body, the effects will vary... the most dangerous path is for the current to travel through your heart.  Since your Heart is a muscle and is is controlled by an "electrical" signal, this extreme voltage can cause an over fibrulation of the cardiac muscles and essentially render then useless... kind of like if you were to take a slinky and stretch it out as fa as you can... its not goign to contract again, and is not something that can be easily fixed.  Hope this helps!
487275
Further reading of the reference given in answer 3 motivates this WARNING:\nA given AC current has greater biological/neurological effects than DC. 15 ma is enough to cause "Shock--painful, severe effects: muscular contractions, breathing difficulty". Also,"The threshold for a painful shock, in which muscles cannot let go, is 10.5 mA for AC current."\nJust in case this information inspires experimentation.
174207
I think the electricity from the taser causes causes your all of your nervous cells to trigger all at once.  When a nervous cell is triggered it needs some time to recover before it can send another signal, so if all of your cells are in this recovery stage then I guess this is why it would incapacitate a person for a limited time.
114222
Fur rubbed on plastic or glass is a classic way to make a static shock.  By wearing those gloves and turning the steering wheel, you are building up a good bit of electricity.  Don't drive with those gloves on.
761926
its pretty simple, depending on the shock level you want. use a industrial plastic glove. with a small metal plate on the thumb and middle finger(make sure u don't touch them together) and hook up a circuit with high voltage and low amps. if amps are too high you will hurt someone fatally. circuit kits are available at local stores. this can be very dangerous, be careful. use only small shock devices.
254345
Brian's answer is correct.\nThe 'shock' you feel is the flow of electric current through your muscles.\nBut voltage is a measure of how much potential the electric source has - the higher the voltage, the more current will flow through you when you hold the terminals. The relationship between the voltage and current is known as Ohm's law. V=I*R. Where R is the resistance between the two terminals (your body, perhaps).\nYou can die with just a few milliamps (1 amp = 1000 milliamps) of current passing through your body IF it flows through your heart (and for a certain length of time). It will induce fibrilations as it interferes with your normal heart electric current.\nHaving said all that, you can feel voltage too without causing current to flow - in the form of your hair standing on end. You need a lot of voltage (thousands of volts) to cause that sort of effect.\nAnd that brings up the next question, why doesn't regular static electricity kill you? It has thousands of volts, so why does it not cause amps to flow through your body (and heart) and kill you? Well, in most normal circumstances the quantity of charge (number of electrons) is very very small - so the current flows for only the briefest of moments and doesn't do any harm to a normal person. However, if you have a pacemaker then you can kill the device and so kill the person! Electronic circuits are typically far less robust than the human body in this circumstance.
969863
There is also friction caused by the turning of the gears.  The pendulum need enough mass to overcome this.
24264
Electric current flows between two points, if the points have different potentials. When a bird touches a wire, the bird will have the same potential as the wire.\n\nIf the bird reaches two wires at the same time, there can be different potentials, so the bird can be 'electrocuted'. That's why the wires need to be far enough from each other.\n\nIf somebody reaches the wire and the ground at the same time, there can also be different potentials... That's why the wires need to be far enough from the ground.
454742
An electric shock can occur upon contact of a human or animal body with any source of voltage high enough to cause sufficient current flow through the muscles or nerves. The minimum detectable current in humans is thought to be about 1 mA. The current may cause tissue damage or heart fibrillation if it is sufficiently high. When (and only when) an electric shock is fatal, it is called electrocution.\n\nAn electric shock is usually painful and can be lethal. The level of voltage is not a direct guide to the level of injury or danger of death, despite the common misconception that it is. A small shock from static electricity may contain thousands of volts but has very little current behind it due to high internal resistance. Physiological effects and damage are generally determined by current and duration. Even a low voltage causing a current of extended duration can be fatal. Ohm's Law directly correlates voltage and current for a given resistance; thus, for a particular path through the body under a particular set of conditions, a higher voltage will produce a higher current flow.\n\nShock effects:-\nPsychological\nThe perception of electric shock can be different depending on the voltage, duration, current, path taken, frequency, etc. Current entering the hand has a threshold of perception of about 5 to 10 milliamperes (mA) for DC and about 1 to 10 mA for AC at 60 Hz. Shock perception declines with increasing frequency, ultimately disappearing at frequencies above 15-20 kHz.\n\nPhysiological:-\n\nBurns:- Tissue heating due to resistance can cause extensive and deep burns. High-voltage (> 500 to 1000 V) shocks tend to cause internal burns due to the large energy (which is proportional to the square of the voltage) available from the source. Damage due to current is through tissue heating.\n\nVentricular fibrillation:- A low-voltage (110 to 220 V), 60-Hz AC current traveling through the chest for a fraction of a second may induce ventricular fibrillation at currents as low as 60mA. With DC, 300 to 500 mA is required. If the current has a direct pathway to the heart (e.g., via a cardiac catheter or other electrodes), a much lower current of less than 1 mA, (AC or DC) can cause fibrillation. Fibrillations are usually lethal because all the heart muscle cells move independently. Above 200mA, muscle contractions are so strong that the heart muscles cannot move at all.\n\nNeurological effects:- Current can cause interference with nervous control, especially over the heart and lungs. When the current path is through the head, it appears that, with sufficient current, loss of consciousness almost always occurs swiftly. (This is borne out by some limited self-experimentation by early designers of the electric chair. and by research from the field of animal husbandry, where electric stunning has been extensively studied)\n\nPoint of Entry:-\n\nMacroshock Current flowing across intact skin and through the body. Current traveling from arm to arm, or between an arm and a foot, is likely to traverse the heart, and so is much more dangerous than current traveling between a leg and the ground.\n\nMicroshock Direct current path to the heart tissue
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This is an old trick my high school sports trainer taught me... get a tuning fork and give it a whack and while it is vibrating touch it to the end of your thumb... if it hurts really really bad then it is broken...if it only stings a bit then it is not broken.
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I have a friend that recently went through police training. One thing that they had to do was...\n5 trainees stood side by side and interlocked their elbows. The trainee at either end were given a wire each to hold onto and they were then hit with a taser jolt which had an equal effect on each of them.
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I just recently got braces and the answer is NO! only when the wire gets longer in the back of your mouth does it hurt, it only happens as your teeth get straighter, and at your next appointment they can clip the wire for you. and I don't know what you all mean about getting them tightened, cause I haven't had mine tightened yet, and If I have it doesn't hurt at all,(obviously it doesn't hurt if I didn't even notice!!)You have nothing to worry about. But as your teeth straighten they will hurt a little bit, and it will be hard to eat, just take some ibuprofen, 'cause it's a muscle relaxer and it will help. So take a deep breath and breathe. It's not as bad as some people make it out to be at all. Good Luck, I hope this helped. anymore questions Email me at, jordan_smith_is_the_best_32@yahoo.com
311533
I believe the external stimulation would trigger a contraction.  I am basing that on the fact that the muscle fibers are stimulated directly by the electrical current\nfrom the voltage source.\n\nRecruitment of fibers occurs opposite the standard.  Type II, fast twitch fibers, are recruited first and Type I, slow twitch, are second.  Normally the pattern is Type I then Type II when needed.\n\nThe change in charge at the muscle, which is a great conductor of electricity, causes the Ca++ release normally triggered by ACh or another neurotransmitter.\n\nCouldn't find a source to back me up, try an advanced physiology textbook. I did find this link below that has similar information.
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not neccessarily, it really depends if your wearing shoes or not. of course your asking, how do i verify this?\n\nwell their is this thing called conductors and instulators. conductors means current can go through and insulators means it can't. the reason why humans get charged up because their friction causes electrons to build up in their body.\n\nso basically, touch someone else for fun and you might verify that shock.
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During a smash with a hammer two end of a metal show a potential difference. That is piezo electricity.\nDuring the smash electrons are displaced.\n\nTh