Earth, Science

Assignment Help:

Earth

How do we describe the 'big ball' on which we live? Seen from space, it appears as a bluish-white sphere. Its wealth of plant and animal life, snow covered peaks, blue oceans and white clouds make the Earth a beautiful planet. Human beings have explored it extensively. Yet, the first hand knowledge of  the Earth is limited to a thin shell of  rock and water extending to a few kilometres below the surface, and to the atmosphere above. However, using indirect methods, such as the study of waves generated during earthquakes, scientists have been able to picture the Earth's interior. without ever seeing or sampling it. We will now briefly describe the current scientific knowledge about the Earth. 

 

1094_Earth.png

The Earth's  atmosphere has been studied extensively with  the help of ground based experiments, aircraft, rockets and balloons. Though it  is not divided  into distinct layers, it-is helpful to think of  the atmosphere in this way. The troposphere, nearest to the surface,  is made up of  78 per cent nitrogen and 21 per cent oxygen, with water vapour, carbon dioxide, neon and argon making up most of  the remaining one per cent. It has an average temperature of about 16°C at sea level and-  16OC near its top. The stratosphere, coming next contains ozone and has a temperature ranging from -  16OC to -4OC.  This ozone layer absorbs the harmful UV radiations fron, the Sun,  thus protecting us from them. The carbon dioxide in the Earth's atmosphere traps heat and makes it warmer through the greenhouse effect. Were it not for this, the Earth's surface temperature would be much lower and it would always be covered with ice.


Related Discussions:- Earth

Diagnosis-scope of first aid, Diagnosis: 1.  Diagnosis of the casualty ...

Diagnosis: 1.  Diagnosis of the casualty involves considering the history, symptoms and signs. 2.  History is the information as to how the accident or illness occurred.

Health hazard data and the treatments , Here this study gives the health ha...

Here this study gives the health hazard data and the treatments for some of the compressed gases. Generally the standard procedure in gas based accidents is as follows: (1) Remo

Explain hypersecretion (hyperthyroidism) or thyrotoxicosis, Explain the Hyp...

Explain the Hypersecretion (Hyperthyroidism) Or Thyrotoxicosis This condition generally occurs in adult life. This is commonly caused by hyperplasia of the gland and is called

Explain the factors that affect the reabsorption process, Explain the Facto...

Explain the Factors That Affect the Reabsorption Process There are also two major factors that affect the reabsorption process. These include: 1) Concentration of small m

Cell theory, Ask question #Minimumwhat is that definition for cell theory? ...

Ask question #Minimumwhat is that definition for cell theory? 100 words accepted#

Preparation of report for an imaginary accident, Preparation of Report for ...

Preparation of Report for an Imaginary Accident In case of serious accidents, accident report has to be sent to the Head of the Institution who may use it for official purposes

Composition of bile - liver and bile stored in gall bladder, Composition of...

Composition of Bile - Liver and Bile Stored in the Gall Bladder There is a slight difference between the composition of bile produced by the liver and bile stored in the gall b

Mineral to be strongly magnetic other than magnetite, What is the only usua...

What is the only usual mineral to be strongly magnetic other than magnetite: Pyrrhotite

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd