PPT: Some Natural Phenomena | Science Class 8 PDF Download

 Page 1


Some Natural 
Phenomenon
Page 2


Some Natural 
Phenomenon
Introduction
Definition
A Natural Phenomenon is 
anything that occurs on 
its own in nature without 
any kind of human 
intervention.
Examples
Weather patterns, fog, 
storms, winds, tides, 
volcanic eruptions, and 
cyclones all can be 
categorized as natural 
phenomena.
Our Focus
In this chapter, we will explore how these natural 
phenomena occur and learn important ways to protect 
ourselves and reduce the harm they can cause.
Page 3


Some Natural 
Phenomenon
Introduction
Definition
A Natural Phenomenon is 
anything that occurs on 
its own in nature without 
any kind of human 
intervention.
Examples
Weather patterns, fog, 
storms, winds, tides, 
volcanic eruptions, and 
cyclones all can be 
categorized as natural 
phenomena.
Our Focus
In this chapter, we will explore how these natural 
phenomena occur and learn important ways to protect 
ourselves and reduce the harm they can cause.
L i g h t n i n g
Lightning is a natural electrical discharge in 
the atmosphere that usually happens with 
thunder. It's similar to electric sparks we see 
on loose electric poles or insecure plugs, but 
on a much larger scale.
Lightning often occurs during thunderstorms, 
volcanic eruptions, or dust storms. It happens 
when two clouds bump into each other or 
slide past one another, generating a large 
amount of electric charge - similar to rubbing 
a comb through dry hair.
When clouds collide, they create bright 
flashes in the sky - what we call lightning. 
Once a cloud becomes electrically charged, it 
releases that charge down to the earth.
In simple terms, the earth absorbs this 
charge, which helps to balance the electric 
charge of the cloud, completing the electrical 
circuit between sky and ground.
Page 4


Some Natural 
Phenomenon
Introduction
Definition
A Natural Phenomenon is 
anything that occurs on 
its own in nature without 
any kind of human 
intervention.
Examples
Weather patterns, fog, 
storms, winds, tides, 
volcanic eruptions, and 
cyclones all can be 
categorized as natural 
phenomena.
Our Focus
In this chapter, we will explore how these natural 
phenomena occur and learn important ways to protect 
ourselves and reduce the harm they can cause.
L i g h t n i n g
Lightning is a natural electrical discharge in 
the atmosphere that usually happens with 
thunder. It's similar to electric sparks we see 
on loose electric poles or insecure plugs, but 
on a much larger scale.
Lightning often occurs during thunderstorms, 
volcanic eruptions, or dust storms. It happens 
when two clouds bump into each other or 
slide past one another, generating a large 
amount of electric charge - similar to rubbing 
a comb through dry hair.
When clouds collide, they create bright 
flashes in the sky - what we call lightning. 
Once a cloud becomes electrically charged, it 
releases that charge down to the earth.
In simple terms, the earth absorbs this 
charge, which helps to balance the electric 
charge of the cloud, completing the electrical 
circuit between sky and ground.
The Sparks that the Greeks 
Knew About
Ancient Discovery
Around 600 B.C., 
ancient Greeks 
observed that 
rubbing amber with 
fur attracted light 
objects, an early 
observation of static 
electricity.
Franklin's Insight
In 1752, Benjamin 
Franklin 
demonstrated that 
lightning and static 
electricity sparks 
are essentially the 
same phenomenon, 
a realization that 
took nearly 2,000 
years.
Everyday 
Examples
When you remove 
woolen clothing and 
hear crackling 
sounds, or when a 
plastic scale 
attracts paper bits 
after rubbing on dry 
hair, you're 
witnessing the same 
electrical properties.
Page 5


Some Natural 
Phenomenon
Introduction
Definition
A Natural Phenomenon is 
anything that occurs on 
its own in nature without 
any kind of human 
intervention.
Examples
Weather patterns, fog, 
storms, winds, tides, 
volcanic eruptions, and 
cyclones all can be 
categorized as natural 
phenomena.
Our Focus
In this chapter, we will explore how these natural 
phenomena occur and learn important ways to protect 
ourselves and reduce the harm they can cause.
L i g h t n i n g
Lightning is a natural electrical discharge in 
the atmosphere that usually happens with 
thunder. It's similar to electric sparks we see 
on loose electric poles or insecure plugs, but 
on a much larger scale.
Lightning often occurs during thunderstorms, 
volcanic eruptions, or dust storms. It happens 
when two clouds bump into each other or 
slide past one another, generating a large 
amount of electric charge - similar to rubbing 
a comb through dry hair.
When clouds collide, they create bright 
flashes in the sky - what we call lightning. 
Once a cloud becomes electrically charged, it 
releases that charge down to the earth.
In simple terms, the earth absorbs this 
charge, which helps to balance the electric 
charge of the cloud, completing the electrical 
circuit between sky and ground.
The Sparks that the Greeks 
Knew About
Ancient Discovery
Around 600 B.C., 
ancient Greeks 
observed that 
rubbing amber with 
fur attracted light 
objects, an early 
observation of static 
electricity.
Franklin's Insight
In 1752, Benjamin 
Franklin 
demonstrated that 
lightning and static 
electricity sparks 
are essentially the 
same phenomenon, 
a realization that 
took nearly 2,000 
years.
Everyday 
Examples
When you remove 
woolen clothing and 
hear crackling 
sounds, or when a 
plastic scale 
attracts paper bits 
after rubbing on dry 
hair, you're 
witnessing the same 
electrical properties.
Charging by Rubbing
Electron Transfer
Rubbing objects together causes 
electron transfer, creating an 
electrical charge imbalance on both 
surfaces.
Everyday Examples
A rubber balloon rubbed with fur 
attracts electrons from the fur, 
leaving the balloon with excess 
electrons and the fur with a deficit. 
Similarly, plastic combs gain charge 
when rubbed through dry hair.
Charged Objects
Objects that gain or lose electrons 
become charged and can interact 
with other objects through 
electrical forces.