Today we will see interesting topic essay on albert einstein. The greatest German physicist of the 20th century.

**Albert Einstein (1879-1955)**

**Albert Einstein Biography in English** Albert Einstein, known as the most important scientist of the 20th century, did unique research at the fundamental level in physics.

In a few words, his important discoveries were –

1) Botanist Robert Brown et al. S. It was seen in the year 1828. Einstein showed that behind this ‘Brownian motion’ there is movement of liquid molecules here and there.

2) He also solved the mystery of the effect known as ‘photoelectric effect’ and proved that light is in the form of waves as well as in the form of particles.

3) His theory of Special Relativity, a new method of measuring Earth’s time, was revolutionary because it shook the physical ideas of Earth’s time that had been intact since Newton’s time.

4) Further, his theory of general relativity defined gravity more successfully than Newton’s theory of gravitation.

## Albert Einstein Born

**Einstein **was born on **March 14**, **1879 **in Ulm, Germany. The first five decades of his life were spent in Europe in Germany, Switzerland and Czechoslovakia. He then sought refuge in the United States to escape the persecution of Jews under the Nazi regime in Germany. There he spent the rest of his life at the Institute of Advanced Study in Princeton.

## Albert Einstein Information

By the end of the 19th century, most of the problems in physics had been solved and it was becoming popular among scientists that physics was nearing completion. Newton’s laws of motion and gravitation, Faraday-Maxwell’s model of electromagnetism, Kelvin-Boltzmann-Maxwell’s theory of thermodynamics could effectively account for most natural and experimental phenomena. But in the early 20th century, it became clear that this perception was false. Einstein’s contribution was important in bringing about this ideological revolution.

In 1900, the German scientist Max Plack, while explaining the equilibrium state of a confined black hole, postulated that light is microscopically in the form of ‘clusters’ – each cluster having energy proportional to its frequency. Plack’s conclusion was a foreshadowing that Newton-Maxwell’s laws do not apply at the microscopic level.

Similarly, an experiment that caused confusion about the speed of light was done in 1887 by A.A. Michaelson and E. W, Mole was done by this scientist. Newton’s laws of motion predicted that the Earth rotates on its axis from west to east, which should affect the speed of light. For example, light was expected to take different time periods to travel the same distance east-west-east and north-south-north (the first trip taking slightly longer). Michelson-Marley experimentally proved that both journeys take the same amount of time. How will this experiment be rationalized? Fitlarold, Lorenz and Poncaré, the then scholars, had pondered a lot on it, but no satisfactory answer was found.

In the nineteenth century the basic structure of matter in the form of atoms and molecules this idea was becoming a norm. However, she was opposed by some eminent scholars like Arst Mach. He used to say that no matter how many small parts the matter is divided into, it will not appear as such elementary particles. In this background, the year 1905 should be called the most important year in Einstein’s life in terms of achievements. At that time he was working in a small position in a patent office in Bern Switzerland. He was not yet famous as a scientist. But in 1905 he published three papers on the photomagnetic effect and caused a sensation in the scientific world. The first three discoveries mentioned above were in this thesis.

Einstein (albert einstein) considered the continuous random motion of molecules in a liquid in a deep causal analysis of Brownian motion. Due to the continuous impact of such particles, microscopic particles suspended in the liquid appear to move. The findings of this thesis supported the idea that the core of matter is composed of atomic molecules. In the photoelectric effect, when light rays are cast on metals Electrons appear to be ejected from metals due to exposure to light at a certain frequency. In explaining this, Einstein took Plaque further and claimed that light rays are made up of microscopic particles Einstein named them photons – and that the energy of each particle depends on its frequency according to Plaque’s law.

An electron will be ejected only if the emissive particle has the necessary energy to ‘lift’ it from the surface of the metal, otherwise not. From this, it appears that only emitters at certain frequencies can eject electrons. This was the beginning of quantum theory – quantum theory states that the motion of particles at the microscopic level is not governed by Newton’s laws. Einstein (albert einstein) won the Nobel Prize in 1921 for this discovery.

But Einstein’s world fame came from his third and fourth discoveries – the theory of relativity. So Einstein’s relativity became an equation. While treating Maxwell’s electromagnetic theory in 1905, Einstein found two findings that were inconsistent with Newtonian geochronology. These conclusions were 1 the laws of electromagnetic theory are the same for any inertial observer and 2 the speed of light must be the same for any inertial observer. Now let’s see how the contradiction with Newton arises.

An inertial observer is an observer on which no force acts. Its speed is always constant – there are no ups and downs. This means that any inertial observer will find any other observer moving in a certain direction at constant speed. Suppose A sees observer B coming towards us at a speed of 10 km per hour. At the same time a motorcar towards A is traveling on the same road at 50 kmph. A sees that it is coming fast. What will B see? 50-10 = 40 km per hour behind the car. He sees that speed will overtake us. That means the speed of the same car at A is 50 kmph. So B is 40 kmph. appears But the speed of light should appear the same to both. Conversely, even if a light ray is traveling from B to A along the same path as the car, then A should feel its speed slightly greater than B, according to Newton’s laws of space-time measurement.

To eliminate this contradiction, the rules of space-time measurement must be changed and Einstein explained how to change them by presenting mathematics. We assume that A and B’s clocks measure time at the same rate. But it does not happen according to Einstein’s law. A will feel that B’s watch is running slightly slower, and A will see that the treadmill B is holding in the direction of his speed is slightly skewed, and ironically, B will have the same diagnosis about A’s watch and treadmill.

This conclusion was confusing not only to the common man but also to the scientists and hence people were not ready to accept this new theory of relativity. But after the experiment, the truth of this was confirmed. This theory was confirmed by the Michelson-Moll experiment, the existence of the muon particle in cosmic rays, and the process of high-energy spinning particles. An important conclusion that emerges from it is that E = Mc²- i.e. mass multiplied by the square of the speed of light, which gives the answer is the amount of energy required to destroy an object of mass M. This conclusion was proved in the destructive form of atomic bomb.

## Albert Einstein’s definition of gravity

Between 1905-1915, Einstein (albert einstein) proposed a new law of gravity. What is gravity? Einstein’s answer to this question is as follows: The effect of mass on space-time is gravity; This results in changing the geometry of space. Laws of geometry are conclusions about measurements. For example, Euclid’s geometry states that the sum of three angles of a triangle equals two right angles. According to Einstein, if a light ray were to draw a triangle around the sun, the sum of its three angles would add up to slightly more than two right angles.

Even the idea of this changing geometry which is sometimes phrased as space is curved seemed incomprehensible to most. But even though it was not possible to draw a triangle around the sun to confirm its truth, it was proved that the path of light rays is changed due to its gravity when it passes by the sun. During a Khagras solar eclipse, the direction of the star behind the Sun is slightly changed. During the solar eclipse of 1919, scientist Eddington proved this by conducting observations at two places. That historic experiment brought immense fame to Einstein. Of course, general relativity has been tested in many ways since then, and the theory has been successful.

Einstein (albert einstein) won the Nobel Prize in 1921 for his discovery of the photoelectric effect. He should have won this prize (twice) for both theories of relativity. But even after its full use, there were occasional controversies about the theory of special relativity, while many tests of the theory of general relativity took place after his death. Despite his early contributions to quantum theory, Einstein (albert einstein) remained skeptical of some of the fundamental foundations of the theory until the end. His debate with quantum scientist Niels Bohr on this subject is famous. Due to his doubts, he remained aloof from the further development of this theory. He spent the rest of his life (at the prestigious Institute of Advanced Study at Princeton) trying to unify gravitation and electromagnetism. In this case too

He remained aloof with regard to new developments in physical science. Eminent scientists of that time were of the opinion that such integration was not possible. But unfortunately, the scientific research devoted to basic physics today is moving towards unification by changing the fashion! These unification efforts are by different means but the inspiration behind them is Einstein’s, that is, the dealings of nature

By a single root action – we see its various forms. But anyone would agree that Einstein’s (albert einstein) research in the decade 1905-15 was lasting and revolutionary. He regretted till the end that his research resulted in a destructive weapon like atomic bomb. Because he was not only a supporter of the humanistic approach, going beyond the usual ritualistic religion, but also a role model in actual action.

## Albert Einstein Class 11 MCQ

### albert einstein at school question answer

**What field of science is albert einstein most famous for?**

A) Biology

B) Chemistry

C) Physics

D) Astronomy

**Answer:** C) Physics

**Einstein’s famous equation, E=mc², is related to which concept?**

A) Gravity

B) Energy and mass equivalence

C) Electricity

D) Magnetism

**Answer:** B) Energy and mass equivalence

**In which year did albert einstein publish his theory of relativity?**

A) 1905

B) 1915

C) 1925

D) 1935

**Answer:** B) 1915

**What is the name of the theory that describes the bending of light in a gravitational field, proposed by Einstein?**

A) Quantum theory

B) Special relativity

C) General relativity

D) Atomic theory

**Answer:** C) General relativity

**Which of the following did Einstein receive the Nobel Prize in Physics for?**

A) Theory of Relativity

B) Photoelectric Effect

C) Quantum Mechanics

D) Brownian Motion

**Answer:** B) Photoelectric Effect

**Einstein was born in which country?**

A) Germany

B) United States

C) Switzerland

D) Austria

**Answer:** A) Germany

**What was albert einstein**‘

**s profession besides being a physicist?**

A) Mathematician

B) Painter

C) Musician

D) Philosopher

**Answer:** C) Musician

**Which famous equation is associated with the relationship between energy (E) and frequency (ν) of light?**

**A) E=mc²**

**B) E=hf**

**C) F=ma**

**D) PV=nRT**

**Answer:** B) E=hf (where h is Planck’s constant and f is frequency)

**What is the name of the famous thought experiment involving Einstein’s elevator?**

**A) Newton’s Cradle**

**B) Galileo’s Pendulum**

**C) Einstein’s Carousel**

**D) Einstein’s Elevator**

**Answer:** C) Einstein’s Carousel

**Which famous document did Einstein famously sign in 1939, urging the U.S. to develop atomic weapons?**

A) The Declaration of Independence

B) The Treaty of Versailles

C) The Manhattan Project Agreement

D) The Einstein-Szilárd Letter

**Answer:** D) The Einstein-Szilárd Letter

**What is the term for the phenomenon where an observer experiences time passing more slowly in a strong gravitational field?**

A) Time Dilation

B) Time Contraction

C) Time Expansion

D) Time Compression

**Answer:** A) Time Dilation

**In addition to the theory of relativity, Einstein made significant contributions to understanding the nature of which particles?**

A) Electrons

B) Protons

C) Photons

D) Neutrons

**Answer:** C) Photons

**Which famous scientist was a close friend and collaborator of Einstein, and together they developed the Bose–Einstein statistics?**

A) Max Planck

B) Niels Bohr

C) Satyendra Nath Bose

D) Werner Heisenberg

**Answer:** C) Satyendra Nath Bose