Almost 12 years ago, in 2006, The British Medical Journal had highlighted a case of a 15-year-old girl who left with severe injuries after being struck by lightning while talking on her phone. The journal recommended not to use the mobile phones during lightning. In addition, they quoted Australian Lightning Protection Standard to back their claim. The last part of the journal read like this -
This rare phenomenon is a public health issue, and education is necessary to highlight the risk of using mobile phones outdoors during stormy weather to prevent future fatal consequences from lightning strike injuries related to mobile phones.
The Australian Lightning Protection Standard recommends that metallic objects, including cordless or mobile phones, should not be used (or carried) outdoors during a thunderstorm.5 We could not find any advice from British telecommunication companies.
Source - British Medical Journal
The most reputed News Broadcaster BBC had reported this event on their Website then . This news was vehemently doing the rounds on internet all over the world. Later, The Australian Mobile Telecommunication Association (AMTA) turned down the claim of British Medical Journal saying The claim that mobile phones are a risk when used in a storm is misleading. They came up with a detailed description about this on their Official Website .
The conflict between these two giants distorted the truth when it reached the layman. They leaned towards the former's claim. Is it safe to use mobile phone during lightning? - Contrary to the widespread urban myth,The answer to this question is It is completely safe. I am going to make an attempt to describe what exactly the lighting is and how comes it is safe to use the mobile phones during lightning.
Earlier Beliefs
Early Greeks believed that lightning was a weapon of Zeus. Thunderbolts were invented by Athena, the goddess of wisdom. Since lightning was a manifestation of the gods, any spot struck by lightning was regarded as sacred. Greek and Roman temples often were erected at these sites, where the gods were worshipped in an attempt to appease them. the same way every culture attributed lightning to their own Gods and superstitions.
In Russia, As lately as 1800, when rain was wanted, three men climbed a tree. One would knock two firebrands together; the sparks imitating lightning. Another one would pour water over twigs, imitating rain. A third would bang on a kettle to attract the thunder. And throughout early Europe, church bell ringers would make as much noise as possible, hoping to scare away the storms from these holy dwellings which were struck frequently by lightning. ( Source )
According to the great Greek philosopher Aristotle, thunder was considered to be caused by the collission of clouds and most of the world believed it to be true.Interestingly, This belief continues to be in force to date. Still in many schools this concept is being taught!
What Exactly the Lightning Is?
Lightning is a flash of light created by electro static discharge between the charged regions of the clouds or between the earth and electrically charged regions of the clouds.
It works in the same way the comb that you rubbed with your hand attracts the paper pieces scattered on the table. The lightning is usually produced by Cumulonimbus Clouds.These clouds are heavily densed and contains a large quantity of Ice and water in it. The movement of Ice and water causes collision in between them and This turbulence in turns leads to the creation of electric charges within the cloud. Eventually, negative charges accumulate in the bottom and the positive charges accumulate in the upper side of the cloud.
Image Source - NOAA Public Domain
The cause of charge separation is well explained in This Paper.
Updrafts in the thunder cloud transport small droplets of water upwards. As the droplets rise they cool down but cannot freeze yet. They become supercooled. Meanwhile, big "ice particle", i.e. hail, forms in the cold upper regions of the cloud and falls downwards due to gravity.
When the falling hail collides with the supercooled droplets, the latter freeze instantly, releasing their latent heat to the hail. Thus, the descending hail is always a bit warmer than its environment pushing it towards melting. The hail becomes also supercooled / "soft" and is then referred to as graupel.
Simply saying,the gravity pulls the heavier ice particles downward and the evaporation causes lighter particles to move upward; These particles have negative and positive charges respectively. That means, the cloud is negatively charged in the bottom and positively charged in the top.
These accumulated charges will have the tendency of neutralising each other to acquire a state of stability. In search of opposite charges they form a channel of Ionized air which causes the spark that we see as lightning
Types of Lightnings
Lightnings can be mainly categorised into two types.
1. Intra Cloud and Inter Cloud Lightnings
These are the most common Lightnings.About three quarters of all lightnings never leave the clouds.They don't directly cause any damage to the things on the surface of the earth. Thousands of such storms can be spotted in every single day
Electric discharge occuring within the cloud or in between the clouds is the fundamental cause of this type of lightning. A charged particle easily discovers the oppositely charged particle and forms a channel by ionizing the air between the source of charges which results in what we see as lightning.
2. Cloud to Ground Lightning
A brief explanation is needed here as this variety of lightning is the real Villain. As the name suggests this type is caused by the interaction happening between the charged clouds and the ground. This is dangerous as this type of lightning has claimed thousands of lives until now.
The negative charges accumulated in the bottom part of the clouds tend to discharge to achieve a stable state. For that, they need the help of positive charges. Here, the ground beneath it acts as the positively charged front. the ground can be any territorial part like mountain,tree,Building or a living being. the negative charges start its journey from the cloud in the form of discrete stepped leader.
Image Source - NOAA Public Domain
The flow of negative charges happen with a speed of 200,000 KM/hr. It would be higher if it travels without any intermediary pause. This charges again ramify into so many branches on their way to the destination. The medium they travel is the Air which is a poor conductor. But at the time of thunderstorm it turns into an electric conductor due to Dielectric Breakdown.the air between the cloud and the ground now acts like a capacitor. When the electric field is high enough, the air partially ionizes, at which point there are free electrons to carry current and the air becomes, essentially, conductive.
It is very interesting to note that during Ionization the temperature of Air rises to as high as 20,000 degree Celsius,Which is almost 5 times the surface temperature of the sun!but in no time it cools down,which is one of the causes for thunder!
As the negatively charged stepped leader approaches the ground, it acts as a magnet that attracts positive charges. Initiation of a stepped leader is blind and it ramifies at every 50 metres. The tip of the stepped leader keeps on looking for an easy and closest way to reach the positively charged ground.
The Tallest objects here becomes easiest paths for the negative charge flow to attain the nullification by colliding with positively charged Earth. If a tree is the tallest object,The lightning will strike it.If it is the mountain that is taller in the place where the lightning is about to strike,everything other than the mountain would be safe. As soon as the stepped leader about to touch the ground, a return stroke gets initiated. Which we call as Streamer whose initiation starts from the ground. This is the most brightest part in lightning.
The part I have described upto now is about Negative Cloud to Ground lightning Where the negatively charged stepped leader emerges from the clouds and moves towards the earth to meet the positive charges.This is the very common type of Cloud to Ground lightning. One more type is there which is very rare and most dangerous that the name 'silent killer' would be suitable for it. I'm talking about the Positive Cloud to Ground Lightning in which the positive charges initiate their journey from the clouds and turns the earth into negatively charged Streamer. The ramifications are unlikely to see here as the lightning chooses a straight path. This type of lightning is super dangerous as it can sneak on the observer without even showing a distant sign!
The Thunder
As I nudged earlier,Thunder is mainly caused by the Ionization of the Air. In no time the air is heated up to 20,000 degree Celsius and immediately cools down. This change in temperature causes the air to suddenly expand and then contract.Vibration is formed along the path of lightning and it gets transmitted through the air.It reverberates enough to cause The rumbling. The vigour of thunder differs according to its distance. The near it is to the observer,the louder it gets. As the sound travels in a lower velocity compared to that of light, Thunder arrives much later The arrival of lightning effect. Maybe after one's death!
How Comes using mobile phones is safe during lightning?
As we have discussed, the lightning strikes on someone not because of the person uses mobile phone or he/she wears ornaments made up of conductors. Simply, Such a belief is an urban myth. Rather , It chooses the easiest and closest path to reach the ground. It doesn't at all look for the specific medium as the amount of energy it handles has no time to do so! Moreover, Mobile phones are low power devices using radio waves for its communication.
The radio waves don't need a medium to propagate.That's the reason why it travels even through the vacuum space. The claim that these waves attract lightning to your phone is false. Believe me, It won't attract the lightning or anything like that to your mobile phone!
But, land phones are at high risk as it they are connected by the conducting wires for KiloMetres. Chances of being strucken is very high if you use land phone during lightning!
Conclusion
Using Mobile phone during lightning doesn't attracts the danger. It is completely safe to use. But make sure that you are not standing in a place where your body stands taller than all other objects present there. In such a place, no matter whether you possess a mobile phone with you or not, you will be struck by the lightning. Always seek asylum in a place which is covered and proper earthing is done.
Contrary to the belief that mobile phones attract lightning, Not having one with you may cause danger if you happened to witness or be in such a situation as you will not be able to communicate the danger with others!
Image Sources : Images used here are 'Free to use for Public' and mainly from Pixabay and Wiki
References
About SteemSTEM
steemSTEM is a science community on steemit. Read more interesting science articles under the tag #steemSTEM . Join discord group.
