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

Physical universe, Physical universe: The universe is vast. The Earth w...

Physical universe: The universe is vast. The Earth we live on appears to be just  a speck of dust circling a small star in a remote corner of  an obscure galaxy. If  we are a s

What makes streams look muddy, What makes streams look muddy? After a h...

What makes streams look muddy? After a heavy rainfall have peoples take samples of running muddy water in glass jars. Let the water stand for many hours unless the sediment has

#title. .nasal, why does the nose on some people turn cold and color purple...

why does the nose on some people turn cold and color purple

Explain kaleidoscope brainstorming process, Question 1) What is decisio...

Question 1) What is decision making? Explain the various steps followed to observe effective decision making 2) Explain Kaleidoscope brainstorming process 3) Discuss SWOT Analy

Specific gravity of a liquid not mixing with water, Specific gravity of a l...

Specific gravity of a liquid not mixing with water Pour oil into an open glass tube partially immersed in water until it forces water as far as the lower end. The relative leng

First aid procedures, First Aid Procedures :   Your Counsellor will explain...

First Aid Procedures :   Your Counsellor will explain the first aid procedures through a demonstration session. Carefully observe ali the steps. Try to relate the contents of the f

Define fats - nutritional components, Define Fats - Nutritional Components ...

Define Fats - Nutritional Components Once the body stops eating, it begins to live on its fat. Fat storing depots 'adipocytes' are located in the different parts of the body. I

Explain the organs of the urinary system, Explain the Organs of the Urinary...

Explain the Organs of the Urinary System The figure illustrates the organs of the urinary system. As is evident, the organs of the urinary system consist of 2 kidneys, 2 uret

What is a clinical trial?, Question 1 What is medical evidence? What are t...

Question 1 What is medical evidence? What are the types of medical evidence? What are the precautions should be taken by a medical officer while issuing medical certificate? Q

Flammable solids, Flammable Solids : Flammable solids are substances which...

Flammable Solids : Flammable solids are substances which are flammable or liable to spontaneous combustion or emit flammable gases on contact with water. Examples are: camphor, ci

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