Railway Exam » Railway Exam Study Materials » Geography » WHY IS THE INTERIOR OF THE EARTH HOT?


The article explains the composition and structure of the atmosphere that is similar to a shield under which we can breathe, eat, fulfil our needs, and thus make survival possible.


The interior of the Earth is a significant part of the Earth’s structure that holds the existence of human lives on the planet. The present study has discussed the interior of the Earth and its significance on the stability of the planet. Further, the study has presented the structure of the Earth’s interior in a detailed manner. Additionally, the study has further analysed the importance of Earth’s interior and the main reason behind the hot temperature of Earth’s interior. On a similar note, the study has further discussed the key components that form Earth’s interior and helps in holding lives within the plant. 

What is the interior of the Earth? 

The interior of the Earth is a dense core of the planet made with a molten outer core, a thin crust, and the mantle of the planet. The interior of Earth is generally layered and consists of a hard surface that is commonly called Mohorovicic discontinuity. It is generally placed on the uniform depth of planet Earth and its radius expands about 6 miles below sea level along with 22 miles beneath the surface of the continents. Apart from that, the interior of Earth is divided between the Asthenosphere and the Lithosphere. Geologists use computer modelling and earthquake information in order to know about Earth’s interior meticulously.

Diagram of the interior of the Earth 

The diagram of the Earth’s interior is divided into two significant parts that are the Outer core and the Inner core of the planet. The core of the Earth is composed of liquid on the outward side and solid on the inner side. Minerals like nickel and iron are predominant in the interior of the Earth. The crust of the Earth is divided into two significant parts that are the Continental crust and the Oceanic crust. The diagram of the Earth’s interior maintains the major components of the Earth’s major level like the crust, the inner core, the mantle and the outer core.  

What is the interior structure of the Earth? 

The structure of Earth’s interior is divided into three major components that form the structure of the Earth’s interior. The main structure is divided into the Mantle, the Crust and the Core. The crust is the uppermost part of the Earth with the thinnest layer of 5km to 10km on average. The average depth of the core is 30km with a thickness of 40km in the outer and inner crust of the Earth’s interior. Further, the mantle owns 86% of the total volume of Earth along with an average thickness of 2900km. Finally, the core of the Earth is the innermost part of the planet where it is divided between the inner and the outer core of the planet. 

Importance of the interior of the Earth 

The interior of the Earth is responsible for maintaining the stability of lives on the planet by impacting them on Earth’s surface. Further, detailed knowledge of Earth’s interior can be effective in terms of understanding the Seismic waves successfully which eventually can allow geologists to learn about earthquakes and natural calamities beforehand.   

The reason behind the hot temperature of Earth’s interior 

According to scientists, the average temperature of Earth’s interior is generally 5,000 degrees Celsius which makes it the hottest thing on the planet. The key reason behind the hot temperature can be categorised between two potential factors that generate heat within the planet. First, the planet forms heat and energy on its own which eventually contributes to the way the temperature stays within the planet’s interior. On the other hand, the abundance of radioactive elements is also a major reason behind the hot temperature of the Earth’s interior. 

Components of Earth’s interior 

The interior of the Earth is divided between different layers that maintain the stability of the plant from its core to its crust. The key components of Earth’s interior are categorised into  layers that are listed below. 

  • Crust
  • Core
  • Mantle
  • Asthenosphere
  • Lithosphere
  • Mesosphere  
  • Inner core
  • Outer core 


In conclusion, it can be said that the interior of the Earth is effective in terms of maintaining the flow of life on the planet by providing shelter to all the living beings on the planet. Studying the interior can be helpful in order to predict natural calamities like earthquakes by monitoring the seismic waves. The presence of radioactive elements makes the interior very hot in terms of temperature which primarily is influenced by the movements of the tectonic plates within the Earth. Lastly, the capability of the interior in holding the living beings have made it important in terms of studying Earth’s interior meticulously.


Frequently Asked Questions

Get answers to the most common queries related to the Railway Examination Preparation.

Why is the interior of the Earth hot?

Ans. The interior of the Earth is filled with radioactive elements that emit ...Read full

What is the Earth’s interior mostly made of?

Ans. The Earth’s interior is made of the Crust, the Mantle and the Core...Read full

What are the major ways to learn about the Earth’s interior?

Ans. Monitoring the seismic waves can be effective to learn about the Earth...Read full

Why is magma formed within the Earth’s interior?

Ans. Heat is the main reason behind the formation of magma within the Earth...Read full

Crack Railway Exam with Unacademy

Get subscription and access unlimited live and recorded courses from India’s best educators


Get all the important information related to the Railway Exam including the process of application, important calendar dates, eligibility criteria, exam centers etc.

Access more than

6,505+ courses for Railway Exams 

Get the learning app

Download lessons and learn anytime, anywhere with the Unacademy app