Lightning is a spark of electricity which we see in clouds. 

 

Let’s look at how lightning occurs

 

How does lightning occur?

 

During a thunderstorm, air moves upward and water moves downwards.

 

This leads to separation of charges as follows:

The Positive Charge moves to the Top of Cloud.

And the Negative Charge moves to lower edge of Cloud.

This happens in every cloud.

Since the lower part of the cloud gets negatively charged,

Positive Charge also accumulates near the ground

 

As the magnitude of charges rise over time, 

The air which is a bad conductor of electricity,

Becomes conducting.

 

Now, 3 types of interactions take place

 

  • Inside the cloud

 

The positive and negative charges present in the cloud interact, and cause intracloud lightning.

  • Between two clouds
    The positive charges of one cloud interact with the negative charge of other clouds and cause intercloud lightning.
  • Between cloud and ground
    The negative charge on the lower part of the clouds induces a positive charge in the tall buildings and trees, thus causing lightning.

 

Hence, the Positive and Negative charges meet producing light and sound

This causes lightning.

And the process is called electric discharge.

Lightning - Teachoo.png

 

Note

Air is normally a bad conductor of electricity.

But because of high magnitude of charges, it allows electricity to pass

 

  1. Class 8
  2. Chapter 15 Class 8 - Some Natural Phenomena

About the Author

Davneet Singh's photo - Teacher, Computer Engineer, Marketer
Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.