Saturday, March 14, 2009
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Albert Einstein
Albert Einstein was born at Ulm, in Württemberg, Germany, on March 14, 1879. In 1901, he accepted a position as technical assistant in the Swiss Patent Office. In 1905 he obtained his doctor's degree.
In 1908, he was appointed Privatdozent in Berne. In 1909, he became Professor Extraordinary at Zurich. In 1911, he became Professor of Theoretical Physics at Prague. In 1914, he was appointed Director of the Kaiser Wilhelm Physical Institute and Professor in the University of Berlin. In 1933, he took the position of Professor of Theoretical Physics at Princeton.
After World War II, Einstein was offered the Presidency of the State of Israel, which he declined. He collaborated with Dr. Chaim Weizmann to establish the Hebrew University of Jerusalem.
Albert Einstein's special theory of relativity stemmed from an attempt to reconcile the laws of mechanics with the laws of the electromagnetic field. He dealt with classical problems of statistical mechanics and problems in which they were merged with quantum theory. This led to an explanation of the Brownian movement of molecules. He investigated the thermal properties of light with a low radiation density and his observations laid the foundation of the photon theory of light.
In 1916, he published his paper on the general theory of relativity. During this time he also contributed to the problems of the theory of radiation and statistical mechanics.
In the 1920's, Einstein embarked on the construction of unified field theories. He contributed to statistical mechanics by his development of the quantum theory of a monatomic gas. He also accomplished valuable work in connection with atomic transition probabilities and relativistic cosmology.
In 1921, Einstein was awarded the noble prize and elected as a Fellow of the Royal Society. In 1925, he was awarded the Royal Society Copley Medal. In 1927, he was elected the Fellow of the Royal Society of Edinburgh.
After his retirement he continued to work towards the unification of the basic concepts of physics. Einstein's more important works include Special Theory of Relativity (1905), Relativity (English translations, 1920 and 1950), General Theory of Relativity (1916), Investigations on Theory of Brownian Movement (1926), and The Evolution of Physics (1938). Among his non-scientific works, the most important ones are- About Zionism (1930), Why War? (1933), My Philosophy (1934), and Out of My Later Years (1950).
Albert Einstein received honorary doctorate degrees in science, medicine and philosophy from many European and American universities. During the 1920's, he was awarded Fellowships or Memberships of all the leading scientific academies throughout the world. He gained numerous awards in recognition of his work, including the Copley Medal of the Royal Society of London in 1925, and the Franklin Medal of the Franklin Institute in 1935.
Albert Einstein died on April 18, 1955 at Princeton, New Jersey.
| Honours awarded to Albert Einstein | |
Nobel Prize | 1921 |
| Fellow of the Royal Society | 1921 |
| LMS Honorary Member | 1924 |
| Royal Society Copley Medal | 1925 |
| Fellow of the Royal Society of Edinburgh | 1927 |
| AMS Gibbs Lecturer | 1934 |
| Lunar features | Crater Einstein |
Sir Isaac Newton
Sir Isaac Newton was one of the greatest scientists and mathematicians that ever lived. He was born in England on December 25, 1643. He was born the same year that Galileo died. He lived for 85 years.
Isaac Newton was raised by his grandmother. He attended Free Grammar School and then went on to Trinity College Cambridge. Newton worked his way through college. While at college he became interested in math, physics, and astronomy. Newton received both a bachelors and masters degree.
While Newton was in college he was writing his ideas in a journal. Newton had new ideas about motion, which he called his three laws of motion. He also had ideas about gravity, the diffraction of light, and forces. Newton's ideas were so good that Queen Anne knighted him in 1705. His accomplishments laid the foundations for modern science and revolutionized the world. Sir Isaac Newton died in 1727.
In this lesson you will develop an understanding of each of Newton's Three Laws of Motion.
Newton's first law
According to Newton's first law...
An object at rest will remain at rest unless acted on by an unbalanced force. An object in motion continues in motion with the same speed and in the same direction unless acted upon by an unbalanced force. This law is often called |
What does this mean?
Let's study the "skater" to understand this a little better.
What is the motion in this picture?
What is the unbalanced force in this picture?
What happened to the skater in this picture?
This law is the same reason why you should always wear your seatbelt.
Now that you understand
Newton's First Law of Motion,
let's go on to his Second Law of Motion.
Newton's second law
According to Newton's second law...
Acceleration is produced when a force acts on a mass. The greater the mass (of the object being accelerated) the greater the amount of force needed (to accelerate the object). |
What does this mean?
 |  | |
 |  |
However, the Second Law gives us an exact relationship between force, mass, and acceleration. It can be expressed as a mathematical equation:
or
FORCE = MASS times ACCELERATION
This is an example of how Newton's Second Law works:
Mike's car, which weighs 1,000 kg, is out of gas. Mike is trying to push the car to a gas station, and he makes the car go 0.05 m/s/s. Using Newton's Second Law, you can compute how much force Mike is applying to the car.
Answer = 50 newtons
This is easy, let's go on to
Newton's Third Law of Motion
Newton's third law
According to Newton's third law...
For every actionthere is an equal and oppositere-action. |
What does this mean?
This means that for every force there is a reaction force that is equal in size, but opposite in direction. That is to say that whenever an object pushes another object it gets pushed back in the opposite direction equally hard.
Let's study how a rocket works to understand
Newton's Third Law.
The rocket's action is to push
down on the ground
with the force of its powerful engines, and the
reaction is that the ground pushes the rocket upwards with an equal force.
UP,
UP,
and
AWAY!
You have just learned about
Newton's Three Laws of Motion.
The rocket's action is to push
down on the ground
with the force of its powerful engines, and the
reaction is that the ground pushes the rocket upwards with an equal force.
UP,
UP,
and
AWAY!
DASA
