Lightning: Definition, How is it caused, Do’s and Do Not’s

We all have seen a thunderstorm. When a thick cover of clouds spread over the sky, and we hear scary noises and see the flashes of light passing through the sky followed by rainfall or hailstorm, we call it a thunderstorm. What are these flashes of light that we see go through the sky? That is Lightning! It is one of the most beautiful displays observed in our nature which can be deadly too. It baffled people in ancient times.

The cause of these electric sparks was unknown to them, and they thought it was the wrath of gods punishing them for their sins. Due to the lack of understanding of the cause of these sparks, they were afraid of them. But now we understand it, and that is why we are not afraid of them, but rather, we know what precautions to take to protect ourselves from these deadly sparks.

Sparks and Lightning

We can commonly see lightning flashes when the wires in an electric pole become loose, or the blowing wind shakes the wires. Sparks can also be seen when a plug is loose in its socket. These electric sparks are like mini lightning bolts, or lightning can be understood as a huge electric spark. Sparks were discovered by the ancient Greeks as early as 600 BC. They realized that when a piece of amber was rubbed against the fur, it gained attractive properties and attracted tiny pieces of paper or even hair. In fact, small sparks and crackling sounds can even be heard when we take off woollen or polyester clothes in the dark.

In 1752, An American scientist, Benjamin Franklin, concluded that lightning and sparks on our clothes were basically the same phenomena. However, it took almost 2000 years from the discovery of electric sparks to arrive at that conclusion.

What is Lightning?

Lightning can be defined as a sudden electrostatic discharge between the electrically charged regions of the cloud. Lightning is caused by the accumulation of the charges within the clouds. The temperature of the lightning is around \(27000^\circ \rm{C}\)  (this is six times hotter than the surface of the sun!). When lightning strikes a place, it creates a hole through the air. This hole is called a channel. When the lightning is gone, this hole collapses. The thunder that we hear is created due to the collapse of this hole.  Since the clouds are far from the earth’s surface, the distance between clouds and the ground is large. The speed of light is much greater than the speed of sound, and that is why we see lightning occur through the say way before we hear a rumble of thunder. On earth, the frequency of lightning is around \(40 – 50\) times a second.

How is Lightning Produced?

We know that when two surfaces are rubbed against each other, charges can be produced. The static charges produced by rubbing can either be positive or negative. The like charges repel each other while the unlike charges attract each other, and the movement of electric charges constitutes an electric current. Air currents move upwards while water droplets fall in the downwards direction during the development of a thunderstorm through the sky. Due to this vigorous motion between wind and water, separation of charges takes place. However, the reason behind such a separation is still yet to be understood. Due to the separation of charges, the positive charges get collected close to the upper edges of the clouds.
In contrast, the negative charges get accumulated close to the lower edges of the clouds.  Also, there occurs an accumulation of positive charges close to the ground by induction. As the strength of these charges builds and the magnitude of the accumulated charges becomes huge, the negative and positive charges meet with droplets of water in the air acting as a conductor of this charge. Thus, lightning is created, and we see the streaks of bright light and hear the thunder following it. This process is known as electric discharge.

These charges flow to meet, thus producing strikes of lightning and thunder. A sufficiently high electric potential between two regions and a high resistance medium must be present for this phenomenon to occur. Here it is important to remember that air, in general, is a poor conductor of electricity. Still, due to the accumulation of huge amounts of charges across the sky, air gives up, and it is no longer able to resist the flow of charges, causing the discharge in the form of lightning. This electric discharge can take place between clouds or between the clouds and the earth. Today, we understand lightning and its causes. That is why we are not afraid of it anymore. Lightning can cause huge damage to life and property when it strikes, and therefore it is required that we take proper measures to protect ourselves in case lightning strikes around us.

Safety During Lightning

With voluminous charges discharged through the air, it is not really safe to be in open spaces during lightning and thunderstorms. Make sure to remember the following two points:

1. The sound of thunder, therefore, acts like a safety alarm; you should always rush to a safer place as soon as you hear it.
2. Wait inside the safe place for a while after hearing the last thunder to ensure complete safety.

Safe Place

A safe place is a place that will protect you against any natural disaster. Our homes, made as per the set regulations, are safe places. In schools or other buildings, a room away from open spaces with minimal windows will be the space safe. When travelling in a vehicle like a car or a bus, our place is inside a car with its doors and windows properly locked.

Do’s and Don’ts During a Thunderstorm

It is very important that all people in a region are educated about the safety measures set up by the local government. People should be made aware of their responsibilities in case of such an event.

When you are Outside:

1. Vehicles without a roof of open vehicles, like open jeeps, open cars, motorbikes, tractors, construction machinery, scooters, and bicycles, are not considered to be safe.
2. Open areas like fields, shelters in parks, bus stops, tall trees, places at an elevation do not provide sufficient protection against lightning strokes.
3. It is not recommended to carry an umbrella during thunderstorms.
4. If you are travelling through a forest during a thunderstorm, prefer to take shelter under small trees.
5. If you are in an open field with no proper shelter around, stay away from electricity poles and other metallic objects.
6. Prefer to squat low on the ground in place of lying straight on the ground. To do this, place your hands on your knees and hold your head between your hands. This will ensure the minimum area of your body is exposed to the risk of being struck by lightning.

When you are inside the house:

1. Since lightning is an electrical discharge, it can strike on telephone cords, electrical wires, and even metal pipes.
2. During a thunderstorm, it is safe to stay away from electrical connections involving outside connections. It is advised to use mobile phones or cordless phones.
3. It is not considered wise to call up a person receiving your phone through a wired phone.
4. Evade taking a bath during a thunderstorm. It is better to avoid getting in direct contact with running water.
5. Electric lights can remain switched on since they do not cause any harm, but appliances like TVs, computers, Refrigerators, and AC’s should be unplugged.

Lightning Conductor

The device which is used to protect buildings from the adverse effects of lightning is known as a lightning conductor. A lightning conductor consists of a metallic rod that is installed in the building during its construction. It is ensured that the length of the metallic rod is greater than the height of the building. One end of this rod is kept out in the open at the top of the building, while the other end of the rod is connected to a copper plate that is buried deep into the ground under the building.
When lightning strikes, the rod acts as a passage for transferring electric charge to the ground. Metal columns, electrical wires, and water pipes installed in a building during its construction also protect against lightning to some extent. But it is safe to avoid touching them during a thunderstorm.

Summary

Lightning can be defined as a sudden electrostatic discharge between the electrically charged regions of the cloud. Lightning is caused by the accumulation of the charges within the clouds. In 1752, An American scientist, Benjamin Franklin concluded that the lightning and sparks on our clothes were basically the same phenomena. Due to the accumulation of huge amounts of charges across the sky, air gives up, and it is no longer able to resist the flow of charges, causing the discharge in the form of lightning.

This electric discharge can take place between clouds or between the clouds and the earth. Due to the accumulation of huge amounts of charges across the sky, air gives up, and it is no longer able to resist the flow of charges, causing the discharge in the form of lightning. This electric discharge can take place between clouds or between the clouds and the earth.

Frequently Asked Questions

Q.1. What is lightning?
Ans: Lightning is the electric discharge that occurs through the air during a thunderstorm.

Q.2. What is a lightning conductor?
Ans: A lightning conductor is a device that is installed in buildings to protect them from lightning.

Q.3. How is lightning produced?
Ans: Lightning is produced due to the separation of opposite charges between the clouds or clouds and the earth. As the magnitude of charge builds across the ground and the clouds, the electric current gets discharged through the air, and we see the flash of lightning pass through the air.

Q.4. What measures should we keep in mind during lightning?
Ans: Measures were taken during lightning:
1. As soon as you hear the first thunder, rush to your closest safe place.
2. After hearing the last thunder, wait for some time before stepping out.

Q.5. Why do we see lightning before thunder is heard?
Ans: The speed of light is much greater than the speed of sound through the air. That is why we see lightning before we hear the thunder.

Learn about Conductors & Insulators of Electricity here

We hope you find this article on ‘Lightning‘ helpful. In case of any queries, you can reach back to us in the comments section, and we will try to solve them.