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Indian Famous Scientists (Part 2)

2010-07-16T23:38:00.001-07:00

8. Vikram Sarabhai

Born : August 22 ,1919
Died : December 31 , 1971

Considered the father of the indian space program. Apart from being scientist he was a rare combination of innovator , industrialist and visionary.

9. Anil Kakodkar

He was born on 11 November 1943. Dr . Anil Kakodkar is the great indian nuclear scientist. Currently , He is the chairman of atomic energy commision of india(AECI) and the secretary to the Government of India , Department of atomic energy. He was also director of BhaBha Atomic Research Centre at Trombay.

10. APJ Abdul Kalam

Born - 15 November 1931
The eminent scientist and engineer has also served as the Indian 11th president during 2002 - 2007 . APJ Abdul Kalam is the man who is always full of ideas aimed at the development of India.

11. Birbal SahniBorn : 14 November 1891
Died : 10 April 1949
Birbal Sahni was a renowned palaeobotanist and geologist of India. He is Sahni is credited for setting up the Birbal Sahni Intstitute of Palaeobotany in the state of Uttar Pradesh. In the year 1929 , he received the degree of Sc.D from the University of Cambridge. He was also appointed the fellow of royal society of London , in year 1936 , which is the biggest British scientific honor.

12. Srinivasa Ramanujan

Born : 22 December 1887
Died : 26 April 1920
Srinivasa Ramanujan was a genius mathematician. He is widely believed to be the greatest mathematician of the 20th century. Srinivasa Ramanujan made a significant contribution to the analytical theory of numbers and worked on elliptic functions , continued fractions and infinite series.

13. Dr Shanti Swarup BhatnagarBorn : 21 February 1894
Died : 1 January 1955

A noted scientist of India. His main field is chemistry. His research interests included emulsions , colloids and industrial chemistry reactions. The Bhatnagar - Mathur interface balance , which he
designed along with the physicist R.N.Mathur. This was later manufactured by a British firm. He also composed a beautiful kulgeet (University song) which sang with great reverence prior to functions held in the university.

14. Har Gobind Khorana

Born : 9 January 1922

Har Gobind Khorana is an Americal molecular biologist , who was born to an indian Punjabi family . For his work on the interpretation of the genetic code and its function in protein synthesis, he was awarded the Nobel prize in the 1968.

Famous Indian Scientists (Part 1)

2010-07-16T23:15:00.000-07:00

Indian scientist have played important role in the development of India. After independence in the year 1947 , Indian science has developed very fast and modern way. At present , it spends 0.83 of GNP to the science and technology field.
Here is a brief profile of indian scientists.
1. C.V.Raman

He is one of the most renowned scientists produced by India. His full name was Chandrasekhara Venkata Raman. For his pioneering work on scattering of light , C.V.Raman won the Nobel prize for Physics in 1930.

2. Homi Bhabha

Born : November 30 , 1909
Died : January 24 , 1966

Homi Bhabha , whose full name was Homi Jehnagir BhaBha was famous indian atomic scientist. In independent India , Homi jehnagir BhaBha with the support of Jawaharlal Neru, laid the foundation of scientific establishment and was responsible for the creation of two premier institutions TATA institute of fundamental research and BhaBha atomic research Center. Homi Bhabha was first chairman of India's Atomic Energy Commission.

3. Jagdish Chandra BoseBorn : November 30 , 1851
Died : November 23 , 1937

He was the first prove that plants too have a feelings. He invented wireless telegraphy a year before Marconi patented his invention.

4. Meghnad Saha
Born : October 6 ,1893
Died : February 16 , 1956

Made outstanding contribution to the field of Astrophysics . He put forward an "ionization formula" which explained the presence of the spectral lines.

5. M. Visvesvaraya
Born : September 10 , 1960
Died : April 14 , 1962
Architect of Krishnajasagar dam. Sir Mokshagundam Visvesvaraya was an eminent engineer , statesman and played a key role in building of the modern India.

6. Satyendra Nath Bose
Born : January 1 ,1894
Died : February 4 , 1974

Famous for Bose - Einstein theory. A subatomic particle Boson has been named after him. Honored with "Padma Bhushan". He was an outstanding Indian physicist who is known for his work in Quantum physics.

7. Subrakhmanyan Chandrasekhar

Born : October 19 , 1910
Died : 21 August ,1995

Subrahmanyan Chandrasekhar was one of the greatest scientist of the 20th century. Hi did commendable work in astrophysics , physics and applied mathematics. Chandrasekhar was awarded the Nobel Prize in physics in 1983 by discovering Chandrasekhar limit.

Concept of EMF and current

2010-07-16T12:05:00.000-07:00

EMF is a short form of electromotive force. All the metals contain a large number of free electrons which move randomly in all the directions , inside the metal piece. The electrical force or pressure that causes the electrons to move in a particular direction is called as electromotive force. The units of E.M.F is Volts and EMF is also called as voltage or potential difference. It is denoted by V.

Electircal current is defined as movement of electrons or flow of electrons inside a conducting material. The unit is Ampera(A).The electron current flows from the negative end of the battery to the positive end.

Conventional current is said to be flowing from positive potential to a negative potential. The direction of flow of conventional current is always opposite to that of the electron current.

Relation between charge and current :

Current is defined as the flow of electrons.Higher the number of flowing electrons , higher is the value of current. But each electron carries a constant charge on it. Hence we can define the current as flow of charge per unit time or current is defined as the rate of change of charge with respect to time.

The relation between current and charge can be defined as following mathematical formula:

A current of one ampera is said to be flowing if a charge of one coulomb passes any given point in a conductor in one second. As each electron carries a charge of 1.6*10e(-19) coulomb , one coulomb charge corresponds to 6.25*10e18 electrons. When 6.25*10e18 electrons pass by a point in a conductor in one second , a current of one ampera is said to be flowing through the conductor.

In other words:
1 Ampera current corresponds to flow of 6.25*10e18 electrons.