Spacetime.

Spacetime, or space-time continuum, is a physical model. Space and time exist together.

Length, width, and height-these are what measure space. Millimeters, centimeters, meters, and etc. are units of measurement of space.

Past, present, and future are dimensions of time. Second, minute, hour, day, week, and etc. are units of time measurement.

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Reflection.

Reflection is a physical process. It can be seen in a mirror or in other places.

At the moment of reflection the object appears reflected.

There are different types of reflections, for example, object or sound.

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Rainbow.

A rainbow is a natural phenomenon. It's related to physics.

Red, orange, yellow, green, blue, indigo, and violet are colors of rainbow. These seven colors are in this phenomenon.

A rainbow may appear after rain. Or in the fog. A rainbow can be double.

At night, people may see the lunar rainbow or moonbow.

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Great people: Blaise Pascal.

Blaise Pascal was a French philosopher, writer, scientist, and inventor. He was born on June 19, 1623. His parents were Étienne Pascal and Antoinette Begon.

Pascal was interested in mathematics, physics, and western philosophy. He had his own notable ideas.

Blaise Pascal influenced other philosophers.

He died on August 19, 1662.

Great people: Archimedes.

 Archimedes of Syracuse (Ἀρχιμήδης;) was a Greek scientist. He was interested in mathematics (μᾰθημᾰτικά), geometry (γεωμετρία,), astronomy (ἀστρονομία), engineering, philosophy, and physics (φυσική). 

Archimedes was born on c. 287 B. C., in Sicily. Also, he lived there. Archimedes studied in Alexandria.

This scientist made many important things for science in ancient Greece. There is the Archimedes' principle "Any object, totally or partially immersed in a fluid or liquid, is buoyed up by a force equal to the weight of the fluid displaced by the object." There is a formula bout this principle.

Archimedes said "Eureka!" when he understood it.

"Give me a lever and a place to stand, and i'll move the world" (δῶς μοι πᾶ στῶ καὶ τὰν γᾶν κινάσω) his quote, too.

Archimedes created different scientific writings.

He died on c. 212 B. C., in Sicily.

Great people: Albert Einstein.

Albert Einstein was born on March 14, 1879, in German Empire. His parents were Hermann Einstein and Paulone Koch. Also, Albert had a younger sister Maja.

Since early childhood Einstein was interested in science and books. He studied in different countries including Switzerland and Czechoslovak Republic.

Young scientinst was interested in many sciences, but especially in physics. Albert Einstein studied this subject very deeply. So, he discovered a general theory of relativity. It was very important for modern physics.

Einstein was married two times and had three children. The scientist studied different things and received many awards. Including Nobel Prize of Physics (1921).

Albert Einstein died on April 18, 1955, in New Jersey, the USA.

Great people: Nicolaus Copernicus.

Nicolaus Copernicus was born on February 1, 1473 in Poland. His parents died when he was a child.

Copernicus was very interested in science, especially astronomy. Nicolaus Copernicus could speak and write in several languages, including Latin and German.

Scientist had education in Poland and Italy. He studied mathematics, physics, and astronomy. Nicolaus Copernicus created Copernican principle and Heliocentrism. Also, scientist wrote a book De revolutionibus orbitum coelestium (On the Revolutions of the Heavenly Spheres).

Nicolaus Copernicus did a lot of important things for science during Renaissance.

Copernicus died on May 24, 1543, in Poland.

Chemistry.

Chemistry is one of the most important and interesting school subjects. This science has similar parts with physics. There are many formulas and tables.

H₂O is a formula of water. Students can conduct experiments in special rooms during lessons. 

Chemical elements everywhere. Foods, furniture, our body; all of them have chemical elements.

This science may be difficult for someone. Thanks to chemestry we know about salt, sugar, and fats. It is necessary to know in life.

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Physics.

Physics is one of the hardest school subjects and sciences. Therefore this subject is taught in high schools.

Some laws of phycics have been discovered in ancient times. There are complex physical formulas. Atoms and molecules are an important part of this hard science. Light and electricity work by the laws of physics.

Astronauts must know physics for their work. Ordinary people also should know that science. For example, water is a good conductor of electricity. Electrical items can not be touched by wet hands.

Famous scientists who studied physics: Aristotle, Isaac Newton, Albert Einstein. Today scientists study this science too.

Perhaps physics is more difficult than mathematics. If math is necessary to understand, for physics than physics is more difficult. There is a common subject on physics-chemestry. This science also has complicated formulas.

It was an essay about one of the most complex subjects. Next time will be another.

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