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Prostration the Safest and Tranquillest Refuge from Lightning

Dr. Miah Muhammad Adel

Professor of Physics

University of Arkansas at Pine Bluff

Pine Bluff, AR 71601

adelm@uapb.edu





Lightning is a huge electric spark. It involves momentary neutralization of a huge amount of electric charge.

The neutralization occurs through combination of positive and negative electric charges from separate

locations. This charge neutralization can happen between two parts of the same cloud, two different clouds,

and cloud and ground. The earth receives about 100 lightnings every second. Every year lightning kills more

people than torndoes and hurricanes. These losses take place in open fields near or under trees or around

water. The lightning flash temperature can be 30,000 degrees Celsius. This temperature is five times hotter

than the Sun. The peak current in a lighting strike can be 20,000 amperes [McKenzie, R.,

http://www.agriculture.purdue.edu/fnr/index.html.] As to the global loss, about 24,000 lightning-struck

deaths and about 240,000 lightning-struck injuries occur every year

[http://www.lightningsafety.com/nlsi_history/intl_safety_initiative.html]



Generation of Lightning. Lightning is a neutralization of electric charge in which positive and negative charges

from separate locations combine. This neutralization can happen between two parts of the same cloud, two

different clouds, and cloud and ground. Lightning occurs momentarily. As a result, the details of it are not

commonly observed. It occurs in coumulonimbus clouds the top of which is flat like a nailhead. The

condition for lightning is the creation of positive and negative charges separately in two parts of a

cumulonimbus cloud. It is believed that the charges develop through friction the same way as we develop

charges in our bodies through friction between our feet and a carpet. The layer of positive charges resides

above the layer of negative charges in the cloud. We will discuss the charge neutralization between the

negative charge carrying cloud and the ground.









Fig. 1. Lightnings in the sky.







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Fig. 2. Neutralization of electric charges between a cloud and a tree. Lightning strike on the tree. A

streamer discussed later is pointed by the arrow. Streamers may originate from trees, antennas, flagpoles,

telephone poles, tall towers, people, grass, etc.

(http://www.ux1.eiu.edu/~jpstimac/1400/shockinglecture.html)



A lightning flash consists of a few strokes that take place back to back within a few ten milliseconds. There

may be three or four strokes or even 26 strokes in just two seconds (Serway and Jewet, 2006). We

cannot detect the interval between strokes because of their quick succession. For the same reason, we fail

to detect the intervals between the sequence of pictures on a television or a movie screen.



The strokes are triggered when there is electrical breakdown. At room temperature, electrical breakdown can

occur between two layers of air a meter apart if a voltage difference of 3 million volts is established. In

other words, the electrical breakdown voltage of air is 3 million volts per meter of air (Giordano, 2010).

The electrical breakdown creates pillerlike distributions of negative charges. This is called stepped leader and

approaches the ground. It can travel more than 60 miles in one second. The reason of calling it the

stepped leader is its approach in steps with a speed of more than a million meters per second. It carries a

current of 200 to 300 Amperes. The electrons that make up this current cannot reach the ground in the

shortest straight path. It can make a step forward if the surrounding air has sufficient number of ions

(electron stripped-off atoms) and electrons. The radius of its path is 3 to 4 meters. As the leader

approaches the ground, it breaks down the electrical resistance of the air surrounding any sharply pointed

object. Fig. 3. below illustrates the start and stop steps as the step leaders makes it way toward the

ground. The object on the ground toward which the stepped lleader approaches loses electron because of

the repulsive effect of the electrons with the leader.





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3









Fig. 3. Illustrates the start and the stop steps as the stepped leader shoots towards the

ground. Originally from Lutgens and Tarbuck? The Atmosphere, 8th edition

(http://www.ux1.eiu.edu/~jpstimac/1400/shockinglecture.html)









3

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Fig. 4. The stepped leader induces an ionized channel – neutral atoms are stripped of their electrons

making the electrons free and atoms with positive charges due to losing electrons. Illustrated at the

millisercond interval scale (http://www.ux1.eiu.edu/~jpstimac/1400/shockinglecture.html)



A shortage of electrons makes that object positively charged. The break down of electric resistance causes a

stream of positive charges upward which actually happens because of electrons travelling to ground due to

the repulsion of negatively charged cloud layer. This stream of positive charges triggers the return stroke. At

a height of 20 to 110 meters above the ground the upward moving stream of positive charges and the

downward moving negative charges neutralize – a short circuit is set up between the ground and clouds.



Electrons rain down from the negatively charged clouds. This enoumous amount of falling electrons (about

100 million trillion) carrying about 25 coulomb of electric charge creates 50,000 amperes of current.



Conductivity of the current carrying path lasts for a few thousandths of a second after the return stroke. Any

more negative charges made in the clouds follow the previous established path and creates another new

stroke. Because of straight coming down, it is called dart leader. The approach of the dart leader toward

the ground creates another stroke. And one more bright lightning flash is observed.



Lightning.

Multifarious Problems with Lightning. Lightning is very dangerous. If it hits directly a person or an object

held by the person, the resulting current through his/her body can cause death. If it befalls nearby the

person, side flashes can travel around and reach the person. (The writer had the experience of seeing

whitish patches of light touching the skin to create burning sensation. The side flashes were coming from a

lighting-hit date tree about 100 meters away from his school boarding room. The side flashes were traveling

over a 90-meter wide water body between the date trees and his boarding room). Those floating whitish

fire patches can burn nearby persons if no safe refuge is taken. Also, charge can travel through the

electrically conducting ground to the person. What else more can happen is that due to the induction effect

of the overhead negatively charged clouds, stream of positive charges can flow upward through the body. It

may be estimated that a microcoulomb charge will be induced in the person’s body. What it means is a





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few trillion electrons may leave the body resulting it to be positively charged. The body’s electrical neutrality

is broken down. Depending on how fast this occurs, microcoulomb charge flow can create tens of milliamps

of current. During a lighting strike, when electrons rain down to ground forcefully, atmospheric gas atoms

become ionized and create a lot of positive ions and free electrons. These free electrons can enter the

body to neutralize the upward moving stream of positive charges. It results in a huge current through the

person’s body.



It may be mentioned that the tolerance limit for direct current (from battery sources) for a 70-kg person is

75 milliamperes and for alternating current (from line sources) is 15 milliamperes. For a current within the

tolerance limit, it is possible to release the hands from the source of current although the joint muscles get

squeezed. Also, it depends on the mass of the muscles. (http://www.pat-testing.info/electric-shock.hym) A

current 62 milliamperes is painful for males and 41 milliamperes for females. However, the physical control

over voluntary muscles is not lost (http://www/allaboutcircuits.com/vol_1/chpt_3/4.html).



Lightning Light Colors. Every element has its own characteristic spectrum or emission of light under

appropriate conditions. So do nitrogen and oxygen. Lightning flash shows that it contains many spectral lines

or colors emitted by nitrogen and oxygen. The emission spectra of these gases can be produced in the

laboratory from excitation of their molecules by the application of high electric voltage. This is like the light

emission from commercial neon signs where neon gas molecules contained in a specially designed glass

tube are excited by the application of very high voltage.



Lightning

ightning.

Thunder Associated with Lightning. In the atmosphere, the conductive path for the electric current is set in

steps as said above. Through the stepped arrival, the temperature is raised to 30,000 Kelvin where the

corresponding Celsius temperature is obtained by the subtraction of 273 from the Kelvin temperature. This

temperature converts the atmospheric neutral molecules to plasma in which electrically neutral atoms are

stripped off of their electrons producing positively charged ions and negatively charged free electrons. This

temperature is five times more than the temperature of the Sun. This high temperature increases the air

pressure. The increased pressure causes rapid expansion of the plasma and creates a shock wave. The

thunder associated with a lightning results from this shock wave. It may be said that the air burst like a

huge fire work under that high temperature. The bursting sound travels in all directions from the lightning

area.



Lightning Rod. A lighting rod is a metal rod attached to a house. Its top end is tapering like that of the

bottom of a nail. One end of a wire is connected to it and the other end is grounded. Charges that may

develop on the house flow to the ground through the wire. Storm-causing clouds cannot induce charge on

the house. Electric charges flow to the ground through the rod and wire in case of a lightning strike on the

house. However, when there is a lightning strike, it has been found that a blunt-headed rod works better

than tapered head (Serway and Jewett, 2007).









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6









Fig. 5. Positive charge stream in the air above the roof along metal pipes or wires in the house.

http://ecommons.cornell.edu/bitstream/1813/5168/2/LIGHTNING%20PROTECTION%20FOR%20FARMS.pdf



Distance Estimation to Lightning Strike. It is required to know the distance to the lightning strike to remain

at a safe distance away. The estimation is made from our frequency of breathing per minute and the speed

of sound. We breathe out about 15 times a minute or in 60 seconds. That is we breathe out once every

four seconds. Sound can travel 340 meters in one second. In four seconds, sound can travel 1360 meters

which is almost a mile. However, light travels instantaneously. So, from the product of the counting of the

number of times we breathe out after seeing the lightning and the sound speed of 340 meters or 1,115 ft

per second, we can estimate the distance to the lightning-hit spot. If one hears the thunder in 30 seconds

or in 7/8 breaths after the lightning flash, the person needs to get to a safe refuge. The person should

stay at the safe refuge until he/she passes 30 minutes without seeing any lightning flash. If lightning hits a

very nearby place like 110 meter or 330 ft or less, then a sound like clapping or bursting will be followed

by a loud sound (Ahrence, 2009). And away from a lightning-hit spot, a rumbling sound is heard. The

rumbling sound may be due sound coming from different spots of the lightning. This rumbling noise may be

reflected by mountains and buildings, and thereby weakened.



Lightning Flash Without Thunder Sound. The thunder is created as a result of lightning. That is why it is

natural to hear the thunder after a lightning. However, sometimes we can see the lightning in the sky or a

lightning strike without the thunder noise. The reason is that the thunder noise is refracted or the travel

direction of the noise is changed when traveling through the air. This bends the direction of sound travel

from the straight path. Besides,

the strength of the noise is weakened. Fig. 6 and 7 below illustrates these situations.









6

7









Fig. 6. Lightning flash occurring away from the observer and not toward him.

http://www.lightningphotography.com/favourites.html









Fig. 7. Another example of lightning flash occurring away from the observer and not toward him.





Storms create an unstable condition in the atmosphere. Generally, as we go up atmospheric temperature

goes down. But during a storm, the temperature decrease with height occurs rapidly. Sound propagation

changes its direction in traveling from one atmospheric layer to the next. It may even happen that sound

traveling toward an observer changes its direction and travels upward (Fig. 7) instead of the observer. A

nearby observer may hear the sound but not a far off observer.



Blue.

Bolt from the Blue. It has been said above that a llightning can happen in a number of ways. It can be

within a cloud. It may be from one cloud to the next. It can be between cloud and air. Also, it can be

between cloud and ground. Sometimes a lightning can go away from the cloud to strike an object on the

ground away from the cloud. The lightning does not appear to come from the cloud straight. This is called

a bolt from the blue. Of course, we use it when something appears to happen without a reason.









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Fig. 8. Lightning-struck tree.

http://en.wikipedia.org/wiki/Lightning









Fig. 9. Streamer-hit tree. Trees being the higer objects on the ground, work like

natural lightning rods. http://www.ces.purdue.edu/extmedia/FNR/FNR-FAQ-9-W.pdf



Risk Reduction from Lightning Strike. During lightning, the recommended suggestiosn for protection are the

following:



One needs to take shelter in a brick house. Electric charge can go to the ground using water supply pipes

and current supplying wires (Fig. 5).









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It is suggested not to touch anything even video game lines during a lightning. Wire carrying telephone

should not be used. Wireless phone and cell phones can be used.



Shower can not be taken in the bathroom. Also, cooking utensils cannot be used in the kitchen.



One needs to stay away from any high place, open space, or open water bodies. Charge can flow through

water.



It is advised to stay away from tall trees, electric poles or other tall or long objects. If there is a tall tree,

it is advisable to take shelter in the bushes away from the trees.



It is advisable to stay away from metal things like wire fences, automobiles, buses, trucks or top of trains,

golf clubs, golf cars, umbrellas, farming equipment, etc.



It is advised to turn off electronic equipment like computers, TVs, and other electronic devices. Passage of

heavy electric current can burn them. The author had the experience of getting his custom made computer

and one of his friends got his TV set burned out by lightning strike.



utomobile.

Safety Inside an Automobile. Being inside a car does not offer a guaranteed safety. Modern cars has many

electrical components which favor lightning transfer inside the vehicle. Also, cars with fabric tops or cars that

are made of fiberglass do not offer protection from lightning. A vehicle offers some protection but not 100%

as some people claim (Louis Albornoz, http://www.helium.com/items/200093-safety-tips-lightning-struck-

your-car). The reason of safety in many cars lies in the conductivity of a car’s metal body. The metal

sheets in the automobile is not plane, rather they have curvatures, folds, highs and lows, etc. Electric

charge accumulates on the top surface of the curved of metal bodies. The result is that no charge

accumulation occurs at the bottom side of curved metal surfaces or under the roof of automobiles. If the

passengers in the car touch the ceiling, no charge can flow through their body. However, it is risky to sit

on the rooftops of cars and buses and trains (a common sight in Bangladesh). While inside the car, the

windows have to be closed and no metal parts can be touched. The car should be parked by the

srteetside. Steering wheel, gearshift, and radio cannot be touched. (Hyndman and Hyndman (2009).



and

Refuge Outside Brick Houses and Automobiles. Globally, at any moment people outside outnumber those

inside automobiles. They could be working in the field, walking on foot or travelling in open carriers. For

these people, ther safest refuge is the prostration, the posture closest to Allah Rabbul A’lamin.



The Prophet (peace and blessings be upon him)said that we are nearest to Allah (Subhanallah ta’ala) in

prostration. He has advised us to make more and more du’a in that sate (Ahmad, Muslim, Daud).



The Holy Qur’an mentions of many prostrations in a good number of suras. Allah says in the Qur’an:

“Only those people believe in Our revelations, who, when they are reminded of them, prostrate themselves

in adoration and celebrate the parises of their Rabb and are not puffed up with pride” (As Sajdah,

32:15). Prostration is tied up with our belief.



Also, Allah says: “Do you not see how all who dwell in the heavens and the earth bow down in worship

to Allah, including the sun, the moon, the stars, the mountains, the trees, the animals and a large number

of people. But there are many who deserve the punishment. He who is humbled by Allah has none who

can raise him to honor; surely, Allah does what He pleases.” (Al-Hajj, 22:18). All creations of Allah

prostrate to Him. Worshipping or making prostration to Allah by those objects will not be the same way as

we humans do. We do our way and they do their way.



Further about prostration, Allah says: “O believers! Bow down, prostrate yourselves, worship your Rabb and

do good deeds so that you may attain salvation”. (Al-Hajj, 22:77)





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Furthermore about prostration, Allah says: “Say:”Whether you believe in it or not, it is true that those who

were endowed with knowledge before its revelation fall down and prostrate themselves when it is recited,(107)

and say, “Glory be to our Rabb! Our Rabb’s promise has been fulfilled.(108)They fall down upon their

faces, weeping as they listen, and this increases their reverence”.(109) (Al-Isra’, 17:107-109).



The Prophet (peace and blessings be upon him) of Islam further told us to make prostration in abundance.

Any one that falls in prostration to Allah, He upgrades his status and forgives a sin.



Posture

osture.

Uniqueness and Superiority of the Prostration Posture. Let us see how we can find safety in prostration

from lightning. During a lighting, the taller we stand, the more likely it is to be a source of positive charge

stream as said above. It is not safe either to stand under a tall tree. If lightning strikes the tree, charge

can flow to the ground through the tree and one can be befall in a riskier situation. Also, when traveling to

the ground, charge can jump to a nearby standing person and travel to ground through his body. It is not

safe either to lie on the ground. In this situation, there can be a voltage difference between the feet and

the head when charge flows through the ground. The best secure technique is the least touch with the

ground. This is not achieved in youga or any other kind of sitting. The body needs to be lowered than the

height while in youga or any other sitting. When we recite the tashahood in the sitting after two raka’ or in

the final raka’ of our prayer, still our head remains upright, and we are not at the least height. The best

posture is to go to prostration. In this situation, the highest height one attains is the height from the knee

to the waist inclined at an angle of about 45 degrees. People of average size may have knee to hip a

height of about 50 cm. When this is inclined at an angle of 45 degrees, the actual vertical height becomes

about 35 cm. What touch the ground are the tips of the first two toes, the knees, the palms, the

forehead, and the tip of the nose. For each foot, the first toe tip touches the ground about 4 square cm

and the second toe tip touches about half of that size. Each knee touches about 20 square cm. Each

palm touches about 135 square cm area of the ground. The tip of the nose touches about 0.25 square

cm, and the forehead touches about 2-3 square centimeters. The entire body weight is comfortably

supported by these seven limbs counting the nose and the forehead together. This posture is very

comfortable and peaceful. We cannot squeeze our body any further with any better comfort in any other

posture. The separation between the adjacent sides of the two toes is about 12 cm, the distance between

the adjacent sides of the two knees about 20 cm, and that between the adjacent sides of the palms about

12 cm. The tip of nose and forehead will be about 6 cm apart from either palm. In the open fields, there

will be many things – plants, crops, tall grass, etc – with heights higher than the height in prostration.

Those background objects will be more favored than the person in prostration. Besides, our body does not

have a tall or long shape in prostration like trees, plants, bushes, etc. to be favored by lightning strikes.



Prostration can save us from side flashes in a lightning strike. The reason is that the background and

foreground objects will be higher than the height of the person in prostration, and thus the side flashed can

blocked by those objects.



Prostration is the safest posture from not only a lightning strike, but also a protection from dangerous

currents from a nearby light strike. The reason is that the the current between two points depends on the

difference of the electric voltages between the points - the higher the voltage difference the higher the

current, and the lower the voltage the lower the current provided the resistance remain the same. If the two

points are at the same potential, they have zero voltage difference between the points and no current will

flow. In prostration, either little or no voltage difference is achieved between the limbs touching the ground

as illustrated below.



Let us consider the case in which a person is in prostration and lightning has struck behind him, say, 100

meters away. From the lightning spot, electric charge flow in all direction – front-back, left-right, downward,

and in-between directions. The charge flow will be over a hemispherical volume as shown in Fig. 11a. The

person in prostration (Fig. 11b) will have the two toes at the same distance away from the lighting spot.





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The two knees will be at the same distance away from spot. The two palms, the forehead, and nose will

be at the same distance away from the lightning spot. There will not be any potential difference between

the limbs at the same distance away. As a result no current flows between the two toes. Also, no current

flows between the two knees via the upper halves of the legs and the waist, and no current flows between

the palms via the hands through the chest. As a result, the heart, the most sensitive and vitally important

organ is thereby saved. No current flows from the palms to the head or nose. However, the the left toe

and and the left knee, and the right toe and the right knee will be at different distances. So there will be

a little difference of potential between the toes and the knees. And there will be a little current flow

between the toe and the knee of each leg. We will calculate the amount of current that flows. Similarly,

the left knee and the left palm will be at slightly different distances; so also the right knee and the right

palm. A voltage difference will exist and current will flow from left knee through the left side of the body to

the left palm. Also, a current will flow similarly on the right side of the body. However, the amount of

current between two limbs maintaining a potential difference will depends on (1) the distance from the

lightning strike, (2) the distance between the two limbs, (3) the resistivity of the ground, (4)the electric

resistance of the two limbs, and (5) the strength of the lightning. The amount of current that flows

between two limbs at different potential can be calculated from a simple formula developed in the

introductory physics textbook on electricity. The relationship among these physical quantities can be simplified

and written as

Inter-limb current = [(0.16 x Ground resistivity x lightning current x inter-limb distance having voltage

difference)/(electrical resistance of the the two limbs x square of the distance from the lightning-hit

spot)]

To evaluate this, the steps are to (i) multiple 0.16 and the ground resistivity, (ii) multiply the product in

(i) by the lightning current, (iii) multiply the product in (ii) by the inter-limb distance, (iv) divide the

product in (iii) by the electrical resistance between the two limbs, (v) divide the quotient in (iv) by the

distance between the lightning-hit spot and the object in question, and (vi) divide the quotient in (v) by

the distance between lighting-struck spot and the object, again.



The resistivity of the ground depends on the type of soil – 25 units for loam, 35 units for alluvium, and

300 units for sandy soil. The unit has the name of Ohm-meter. Wet soil has lower resistivity than dry soil

(http://www.eon-

uk.com/distribution/CiCdocs/01%20Technical%20Documents/CN%20Combined/Earthin

g%20Manual/E3%20Earthing%20Manual%20Soil%20Resistivity.pdf). )

Also, different limbs have different electric resistances. A wet body has less resistance than a dry body. In

a dry body the resistance from one hand to the other is taken to be between 15,000 to 50,000 Ohm.

However, the resistance from one extreme end to the other like hand to hand of hand to foot is about

15,000 Ohms (http://www/allaboutcircuits.com/vol_1/chpt_3/4.html) We will take the distance about 100

m between the object and the lightning-struck spot. We take the soil to be alluvium and the average

lightning current 20,000 amperes. For the purpose of illustration, we take this resistance between the toe

and the knee to be half of that between two extreme ends i. e. 7,500 ohms. We can take the toe-knee

distance about 38 cm and knee-palm about distance 33 cm. Let us take 35 cm as the average inter-limb

distance be it toe to knee or knee to palm for the purpose of illustration. Without substituting the object-

lightning distance, we find inter-limb current is about 5/(square of object-lightning distance in meters). We

can substitute the the square of 100 meters distance which is 10,000. We find that the current between

the toe and knee is about 0.5 milli ampere. Because of the higher (at least double)resistance between the

knee and the palm, the current will be about 0.25 milliamperes. The person in prostration may feel tingling

effect only. And it is only in prostration that it can be achieved. Subhanallah! Thus, it is found that the

little current flows through the peripheral part of the body and not through the internal organ. And for no

corrent across the chest. The most vital organ the heart is saved.



Lightning strike



Lightning





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Lightning Current Lightning current









100 meters Fig.10a. Lightning

current flows hemispherically









Fig. 10. Prostration is the best shelter. The top Fig 10a shows that after the lightning strike electric charges

are moving in hemispherical volume. Bottom figure 10b shows the prostration. Three lines drawn through the

person’s limbs indictes that they are at different voltages. The line through the feet is at a higher voltage

than the line through the knees. And the line through the knees at a higher potential than the line through

the pals, nose, etc. The distance between the object and the lightning hit is 100 meters. (Prostration

posture was taken from Ghazi and Ghazi, 2008).



If the person was standing instead of being in prostration, he is under enhanced risk of getting the lightning

struck. It may be mentioned that a day laborer from a neighboring village of the author’s native village was

struck by a lighting when carrying a load of grass over his head. The height of this person including the

load of grass was less than 8 feet. If he would just sit on two feet, his would not be able to lower his

body like the prostration position, and would be under the risk of lightning strike though smaller than when

he is standing.









100 meters Higher Voltage line

Fig. 11a. Hemispherical spread of





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lightning change.



Lower Voltage line









Fig. 11b. A lightning strike on the right of a man in prostration.



Fundamental physicics textbooks mention that lying will not be safe because of the likelihood of a higher

voltage difference between the feet and the head. If the lightning strike would be in the front of the person,

the same situation of current flow as from the lightning strike behind the person would occur. If the lighting

strike spot will be to the left or right side of the person, little current flow will occur between the palm and

nose-forehead on one side of the body and between nose-forehead and the palm on the other side of

the body. Also, there will be little current from one knee to the other knee and from one toe to the other

toe. No current will flow from the toe to knee to palm to fore-head on one side, say the right side, of

the body because they will have the same voltage for being at the same distance away. Similarly, on the

other side these limbs will be at the same voltage but different from that on the rightside.



If someone feels tingle on his body while standing or hair gets straightened upward in open spae, it must

be understood that the person is at a righ risk of having a lightning strike. The reason of hair standing up

is that the negatively charged clouds above his head induces positive charge on his body. An electric field

is set up between the body and the cloud. Due to mutual repulsions, hairs become upright along the

direction of the electric field. Fig.

12 illustrates the situation.









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Fig. 12 Electrification makes hair

upright. http://www.ux1.eiu.edu/~jpstimac/1400/shockinglecture.html



Prostration has other benefits, too. A thumb nail size part of our body is getting more than one cosmic ray

particles every minute. Most abundant of them are muons that carry the same charge as an electron. Our

movements outside our houses or cars determine the accumulation of charges from muons and other cosmic

ray particles. This accumulated charge can be discharged by going to prostration.









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