Most of us fear an electric shock, yet we know little about what is safe and v/hat is not when we handle electricity. For example, most of the time we are cautious about handling electrical devices which seem to be complicated in structure, but do not worry about turning off the 5 electricity with a wet hand. Maybe you don't mind placing your radio
or the hair drier on the wet surface in the bathroom.
Body fluids are not as good conductors as metals. Their resistance is much higher. For example, a current of 20 microamperes flowing directly through the heart can bring about death. On the other hand, a 10 current of 100 to 200 microamperes through electrodes on the chest triggers the regular beating of the heart, after the heart has stopped. The reason for such a big difference in the effects of the two values is that the first current is sent directly to the heart and the second has to pass through the fluids of the body, which have a greater resistance. 15 As you can see, in an electric shock, it is the current that matters, not
the voltage.
One thing about the injuries associated with electric shocks is that, most of the time, they arise from involuntary body movements in response to the current. For example, the current may cause you to 20 lose your balance and to fall off a ladder. Sometimes, the victim freezes with the current, maybe because some muscles are paralyzed for a moment, and he cannot let go of the thing he is holding. As he keeps holding the object, there will be more current sent through the body.
25 One other thing about electric shocks is the burns they cause. When the skin burns, a low resistance path is established for the current and now the current can cause more damage.
Some electrical appliances require earthing. With these appliances, if the insulation becomes frayed, the leakage is carried to the ground, 30 without doing any harm. Most of the time, people use extension cables without the earthing or make incorrect connections. It is not safe to do so. Always use the proper extensions and connections.
One other mistake made by most people is to wind thick wires around fuses, to prevent the fuse from blowing frequently. The fuses 35 are there for safety, to prevent the overloading of the current. If they do not blow, then the excess current may cause damage to the electrical appliances or even cause a fire.
Briefly, it is not safe to play with electricity. Never forget that your body resistance is lowered greatly when it is wet. Always be careful
40 with electricity, but never panic. If you see someone caught up in an electric shock, before you reach out to rescue him, go to the fuse box and shut off the circuit at the main inlet.
A. What do the following refer to? 1. 'they' (line 25):
2. 'if (line 39):
B. Mark the best choice.
1. Line 3, 'cautious' means .
a) ignorant b) curious c) worried d) careful
2. Line 11, 'triggers' means .
a) increases b) starts c) stops d) decreases
3. Line 2 1 , 'freezes' means . a) becomes very cold c) holds on tightly
b) is unable to move d) becomes electrified
4. Line 29, 'frayed' means .
a) worn out b) harmful c) renewed d) overloaded
5. We don't usually worry about turning off the electricity with a wet hand because we .
a) know that it is safe to do so
b) don't mind handling simple electrical devices c) don't fear an electric shock
d) know a great deal about electricity
6. Injuries related to electric shocks are mostly due to the . a) involuntary response of the body to the shock
b) type of appliance in which there was a leak c) voltage of the electric shock
d) Both (b) and (c).
7. Lines 31-32, 'It is not safe to do so' means it is not safe to . a) use extension cables without earthing
b) carry the leakage to the ground c) make incorrect connections d) Both (a) and (c).
1. Why does a low voltage electric current applied directly through the heart cause death while a higher one applied through electrodes on the chest does not?
2. Why does burnt skin enable the current to cause more damage?
3. What kind of misuse of electricity may cause fire?
89
STRESS
Stress is considered to be a natural part of the contemporary world. Everybody is exposed to a certain amount of stress. Nonetheless, it should be made clear that stress doesn't occupy a greater place in our lives today than it did in the past. Although 5 cavemen didn't have to worry about the stock market or the atomic
bomb, they worried about being eaten by a bear while they were 1 asleep or about dying of hunger - things that few people worry much about today. It's not that people suffer more stress today, it's just that they think they do. Everybody thinks that he or she is 10 under the greatest stress. The truth is that everybody actually is under stress because if we really managed to avoid stress completely, we would be dead.
Stress is the response of the body to any demand. Stress is the state you are in, not the agent that produces it, which is called a 15 stressor. Cold and heat are stressors. However, having a highly developed central nervous system, man most frequently suffers from stress due to emotional stressors. The thing for the average 2 person to remember is that all the demands that you make - whether on your brain or on your liver or your muscles or your bones - 20 cause stress. For example, stress can occur under deep anesthesia,
when your emotions are not engaged, or in animals that have no nervous system, or even in plants.
There are two ways of telling when someone is under stress. One, not accessible to the public, is biochemical and neurological -
25 measuring blood pressure, hormone levels, the electric activity of 3 the brain and so on. Nevertheless, there are other indicators that anyone can judge. No two people react the same way, but the usual
responses are an increase in pulse rate and an increased tendency to sweat. You will also become more irritable and will sometimes 3 30 suffer insomnia, even long after the stressor agent is gone. You will
usually become less capable of concentrating and you will have an increased desire to move about.
There are various causes of stress. They differ in various civilizations and historical time periods. At certain times, disease 35 and hunger were the predominant causes. Another, now and then, is 4
warfare or the fear of war. At the moment, the most frequent causes of distress in man are psychological, e.g., lack of adaptation or not having a code of behaviour.
The secret code to coping with stress is not to avoid stress but 'to 40 do your own thing'. It implies doing what you like to do and not
what you are forced to do. It is really a matter of learning how to 5 live, how to behave in various situations, to decide: "Do I really want to take over my father's business or want to be a musician?" If you really want to be a musician, then be one.
A. Find words / phrases in the text which mean the same as the following. 1. modern (paragraph 1):
2. can be seen, noticed by (paragraph 3): 3. signs (paragraph 3):
4. main (paragraph 4): B. Mark the best choice.
1. Line 14, 'if refers to . a) a stressor
b) any demand
c) the agent that produces stress d) the state you are in
2. Line 24, 'One' refers to . a) a way
b) stress c) someone d) blood pressure
C. Mark the statements as True (T) or False (F).
1. There was as much stress in the past as there is today.
3. All symptoms of stress disappear as soon as the stressor agent disappears.
4. The causes of stress have never changed throughout history.
1. Why are emotional stressors the most frequent causes of stress in man?
2. What does the author mean by 'doing your own thing' in the fifth paragraph?