Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Life of a Star:
A young star is thought to be composed largely of hydrogen gas. Hence, the most likely place for a star to be born is in one of the numerous clouds of hydrogen gas that exist in the interstellar space. Stars are now believed to form inside large dense interstallar clouds of gas. It may happen that for some reasons, not fully known so far, a gas 'cloud starts contracting. Under the influence of gravitational pull of the gas, its contraction may continue further. Once such a process begins, a very large volume of gas clouds is affected. As gravity pulls in the clouds, the pressure in the cloud increases. Also, as the cloud contracts, the temperature at its. centre increases. At this stage, it is called a protostar.
When the temperature becomes sufficiently high (about 4 million degrees centigrade), a nuclear reaction starts in the protostar, in which the hydrogen nuclei fuse together to make helium nuclei. In this process a large amount of energy is released. The energy travels to the surface of the star and is radiated in the form of light, heat and other electromagnetic radiation. This energy creates an outward pressure and force. The contraction of the star stops oqly when the inward pull of gravity is balanced by the outward force of this radiant energy. At such a time the star becomes stable in size and temperature. The Sun has been in such a stable situation for the past 5 billion years. Nuclear reactions in the Sun convert about four hundred million tons (4X1014 grns) of hydrogen into helium every second. It is expected that the Sun will remain in thk state for another 5 billion years. As the star consumes a significant percentage of the hydrogen fuel in its core, the nuclear reaction decreases and the outforce of the radiant enem weakens. The core of the star further contracts because its gravitational pull becomes more than the out-force of radiant energy. But this raises the temperature of the core. Meanwhile, the hydrogen nuclei 'burn' in the outer layer or shell surrounding the core. The extra heat from the core as well as the heat generated in the outer layers cause the star's outer region to 'boil' and expand. The star becomes big and its brightness increases. But, as the outer layer expands
what is the implication of the first law on humans
Another aneroid barometer Stretch a piece of thin rubber in excess of the mouth of a small glass jar. Wind thread or string over the rubber to secure it and then put a ring of
what is a soda lime test?
basic steps in callus culture
Immunoglobulin M - Classification of Antibodies Protects against bacteria, gives an early immune response, present on surface of lymphocytes. It stays confined to blood stream
what is mode of nutrition in vulture?
Define the role of Bacteria in soil flora The most abundant soil organisms are primitive, very minute, unicellular organisms devoid of chlorophyll. Bacteria are most abundant i
father of environmental microbiology
QUESTION 1 (a) How did psychology emerge as a separate scientific field? (b) Elaborate on any two schools of Psychology QUESTION 2 Elaborate on the correlational met
Explain Hormonal Phase of Pancreatic Secretion Hormonal phase: After food enters from the stomach to the duodenum, pancreatic secretion starts increasing. Two hormones are resp
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd