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The story of lightning:
  
We have studied about charges and their properties. Now let us relate the charges with lightning.
  • During rain or thunderstorm, air currents move upwards while the water droplets move downwards.
  • In this process, charges also get separated. The positive charges accumulate near the upper edges of clouds, and the negative charges accumulate near the lower edges of clouds.
  • There is an accumulation of positive charges on the ground also.
  • Air is present between the clouds and the ground. Generally, the air is a poor conductor of charges. When the air loses its resistance, it starts to conduct the charges.
  • Negative and positive charges meet, producing streaks of bright light and sound. We see streaks as lightning, and this process is known as electric discharge.
  • The process of electric discharge can occur between clouds and the earth's surface or even between two clouds.

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Charges on cloud and land surface
 
Lightning safety:
  • Walking or standing in an open place during the lightning is not safe for us. A lightning strike could destroy life and property. So, it is essential to take steps to protect ourselves.
  • As soon as the sound of thunder is heard, find a safe place like a building or vehicle. If you are travelling by vehicle, you are safe inside with the windows and doors of the vehicle shut.