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Our bodies are relatively good conductors due to the water in our bodies. Given that larger currents will flow through sections with lower resistance (to be further discussed in the next chapter), electric currents preferentially flow through paths in the human body that have a minimum resistance in a direct path to earth. The earth is a natural electron sink. Wearing insulating shoes, a requirement in many professions, prohibits a pathway for electrons by providing a large resistance in that path. Whenever working with high-power tools (drills), or in risky situations, ensure that you do not provide a pathway for current flow (especially through the heart).

Very small currents pass harmlessly and unfelt through the body. This happens to you regularly without your knowledge. The threshold of sensation is only 1 mA and, although unpleasant, shocks are apparently harmless for currents less than 5 mA. A great number of safety rules take the 5-mA value for the maximum allowed shock. At 10 to 20 mA and above, the current can stimulate sustained muscular contractions much as regular nerve impulses do. People sometimes say they were knocked across the room by a shock, but what really happened was that certain muscles contracted, propelling them in a manner not of their own choosing. (See [link] (a).) More frightening, and potentially more dangerous, is the “can’t let go” effect illustrated in [link] (b). The muscles that close the fingers are stronger than those that open them, so the hand closes involuntarily on the wire shocking it. This can prolong the shock indefinitely. It can also be a danger to a person trying to rescue the victim, because the rescuer’s hand may close about the victim’s wrist. Usually the best way to help the victim is to give the fist a hard knock/blow/jar with an insulator or to throw an insulator at the fist. Modern electric fences, used in animal enclosures, are now pulsed on and off to allow people who touch them to get free, rendering them less lethal than in the past.

Greater currents may affect the heart. Its electrical patterns can be disrupted, so that it beats irregularly and ineffectively in a condition called “ventricular fibrillation.” This condition often lingers after the shock and is fatal due to a lack of blood circulation. The threshold for ventricular fibrillation is between 100 and 300 mA. At about 300 mA and above, the shock can cause burns, depending on the concentration of current—the more concentrated, the greater the likelihood of burns.

Very large currents cause the heart and diaphragm to contract for the duration of the shock. Both the heart and breathing stop. Interestingly, both often return to normal following the shock. The electrical patterns on the heart are completely erased in a manner that the heart can start afresh with normal beating, as opposed to the permanent disruption caused by smaller currents that can put the heart into ventricular fibrillation. The latter is something like scribbling on a blackboard, whereas the former completely erases it. TV dramatizations of electric shock used to bring a heart attack victim out of ventricular fibrillation also show large paddles. These are used to spread out current passed through the victim to reduce the likelihood of burns.

Questions & Answers

With the aid of diagrams,compare the short run equilibrium positions of a perfect competitor and an imperfect competitors
Monlay Reply
What is the term consultation in economics?
Nthabiseng Reply
why is it that the long run Average cost curve does not touch that of the short run curve at its minimum?
Baah Reply
In few words, what is the role of interest rate in economy?
Carlos Reply
what is population
Nyakeh Reply
total number of people in a given area or country
Clement
the total number of people at a given area or country
Clement
total number of people in a given area or country
okhiria
What is price Elasticity of demand?.
Samuel
The responsiveness of the quantity of a commodity demanded to a change in its price, expressed as the percentage change in quantity demanded divided by the percentage change in price.
EMMANUEL
why is it that the long run Average cost doesn't touch the short run cost curve at its minimum?
Baah
what is supply
Precious
please rice and beans will be what type of demand but note we mostly cook it together
Oladosu Reply
complementary or joint demand
Yillah
but did you know you can demand for rice without beans so how is it joint or complementary
Oladosu
From my point of view, rice and beans are replaceable goods, hence they can't be complementary.
Carlos
what are the money value
Wisdom Reply
Nothing more than a purchase power, in other words, $100 now, must have the same value after 1 year.
Carlos
what is Monopoly
Rebecca Reply
what is money
Lawal Reply
It can be define as a big transaction that can control any business for one place to another base.
Akinlo
money is recognisable note to accept both parties selling and buying
Hassan
i don still understan
Rene
hey
Abdul
hi
Rene
money is anything generally accepted as a medium of exchange
Awwal
Money is anything generally accepted as a medium of exchange and for the settlement of goods and services .
Korda
hi good ppl, pls help out
Tumi
discuss human and natural resources as develop strategies ro improving living condition of citizens in developing countries.
Tumi
I don't understand the question.
Naomi
it's a form of currency used for 2 or more individuals or parties in order to reach their amicable personal or business attainment. one must understand that money itself can manifest in multiple fashions for which the individuals or parties adheres.
are u trying to say we shld discuss ways in which human natural resources help in improving living condition of citizens in developing countries?
Naomi
money is a legal thunder generally accepted as a medium of exchange for the payment of debt ,goods and services
Naomi
money is a way of payment.
Carlos
money is any thing that is generally accepted as a medium of exchange good for good and settlement of debt and means of payment
Yillah
money is nothing but a object which is used for exchange of goods and services.
Harshita
money is anything that is generally accepted as payment of goods and services and settlement of debt
Rebecca
what is demand
Melissa Reply
demand is where the customer is willing and able to buy goods and services during a given period of time
idk
demand is the ability and willingness of an individual to buy goods and services at a given price in a particular period of time
Alpha
demand is the ability to buy a specific quantities of goods and services at a given price and at a specific period of time
rosemary
what are the rules of demand
rosemary
Rosemary Nsebon, Do you mean laws of demand?
Alpha
what are the rules of demand
Rene
the rule of demand is the higher the price the lower the quantity demanded and the lower the price the higher the quantity demanded
mbi
thank
Rene
what is unemployment
Rebecca
unemployment is a scenario or a phenomenon in an economy whereby people are willing are able to work but cannot a job
mbi
Suppose you have a team of two workers: one is a baker and one is a chef. Explain why the kitchen can produce more meals in a given period of time if each worker specializes in what they do best than if each worker tries to do everything from appetizer to dessert. please I need a urgent answer
Oladosu Reply
Enables individuals and countries to consume a variety of goods and services
Iddrisu
what is the meaning of competency
Oladosu Reply
competency is an ability and courage to do something perfectly
Abdullahi
ability to perform some task
Segun
rival
Ray
thanks 🙏 it is also the same with the core competency
Oladosu
A sufficient supply
Ebenezer
Ebenezer you mean the (core competency) right?
Oladosu
what is mean,median and mode
Ikeh Reply
mean is the average number of a given data
Gallant
median is the middle number of a given data
Gallant
in a given data sorry
Mitchel
hi
Sajib
Pls am new here
Physcal
what are development bank in Nigeria
Adedigba Reply
.hi
Physcal
hi
Adedigba
hw
Physcal
and cool
Rosie
nice to meet everyone
Rosie
hi how are dears
Mumtaz
how can we development economic in our country
Mumtaz
hi
Charm
Payroll and​ 4p
Wasuroj
Agriculture
Wasuroj
Export
Wasuroj
Transport
Wasuroj
Change management​ and​ cerrancy
Wasuroj
Empoyee
Wasuroj
Lawyer army and​ Lawyer​
Wasuroj
animal husbandry essay
Rakuane Reply
what's the primary location of capital and money market respectively
ALIMI
Difference between extinct and extici spicies
Amanpreet Reply
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Source:  OpenStax, Physics of the world around us. OpenStax CNX. May 21, 2015 Download for free at http://legacy.cnx.org/content/col11797/1.1
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