• Cyclones, storms, winds are some natural phenomena.
  • These phenomena are destructive in nature.
  • Apart from these two other natural destructive phenomena are earthquakes and lightning.

 

Earthing

  1. The transfer of electrical charge can take place from a charged substance to other objects by a metal conductor. On touching the end of a paper clip you will notice that the foil strips will get back to their original state.
  2. On repeating the process, you will observe that the foil paper will meet with each other as you will touch the paper clip.

 

Lightning

  • During a thunderstorm, a bright streak of light with the sound of thunder is called as lightning.
  • Lightning is referred to as the transfer of the charge from cloud to earth or from cloud to cloud.
  • The large-scale electric spark in the sky due to the movements of the water droplets and air current.

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The story of lightning

  • When a thunderstorm forms, the water droplets come downwards and air current goes upwards due to which charges in the clouds separate.
  • The negative charge gathers at the lower part of the cloud and the positive charge gathers at the upper part of the cloud.
  • As the charge accumulation becomes heavy, it becomes unable for the air to resist the flow. This results in the production of the bright light due to the transfer of charges to the ground. This process is known as electric discharge.

 

Dangers of lightning

  • Damage to houses
  • Damage to buildings.
  • Damage to trees
  • Damage to human life
  • Damage to animals

 

Lightning safety

  • Open places are not safe during thunderstorm and lightning. Building or a house is safe.
  • After hearing the first sound this should be taken as an alert. After the last sound does not move out immediately, wait for some time.

 

Dos and don’ts during a Thunderstorm

  1. Open vehicles like tractors, motorbikes, open cars are not safe during the thunderstorm.
  2. Do not carry an umbrella during thunderstorms.
  3. Stay away from metal objects and poles.
  4. Do not take bath during a thunderstorm
  5. Unplug the electric devices like computers, etc.

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Earthquakes

  • Sudden trembling or shaking of the earth for a very short period of time is called an earthquake.
  • When the earth’s crust gets disturbed, it causes an earthquake.

 

Damages due to earthquake

  • Damages to dams, bridges, buildings, and people.
  • Earthquakes cause tsunamis, floods, and landslides.

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Recap

  • Cyclones, storms, winds are some natural phenomena.
  • Apart from these two other natural destructive phenomena are earthquakes and lightning.
  • During a thunderstorm, a bright streak of light with the sound of thunder is called as lightning.
  • Sudden trembling or shaking of the earth for a very short period of time is called an earthquake.
  • When the earth’s crust gets disturbed, it causes an earthquake.