The story of science

This book tells the development of science and introduces great scientists in different eras.

Most people in the renaissance believed in the faith that

1. earth is the center of the heavens. Its habitable surface forms a circle.

2. the stars and other planers are made of substance that could not be found on earth.

3. moon, sun, and stars are revolve around the earth in different spheres.

4. heaven is above the outermost sphere of stars.

5. hell is at earth’s bottom.

These ideas belonged to the pure thought of Aristotle. Ancient Greece believed in him. However, one astronomer named Copernicus was completely against his theory. He believed that

1. earth completes one orbit of the sun each year

2. earth makes a full turn on its axis every day and cause night and day

3. the universe is much larger than anyone has previously believed.

4. our earth is a planet among the others.

Another versatile renaissance scientist is Leonardo da vinci. All of his paintings including last super have never been surpassed. His sculptures are breathtaking. His architectural and landscape designs are farsighted. He was way ahead of his time in anatomy. He dissected dead bodies and learned the way much of the body works. He also designed fanciful flying machines although he was not successful in flying.

Galileo is a star and genius of renaissance, for he unraveled mysteries of motion and astronomy. He had a new concept of studying science which was emphasizing the need for accurate, repeated experiments to test hypotheses. He had lots of contributions:

1. he found that no matter how heavy or light the bob is, it always takes the same time to complete a swing, but if you change the length of the pendulum, the period will change.

2. he dropped two iron balls of the different size and weight simultaneously from the Pisa tower. The result was that two balls crashed on the ground at the same time, which changed ideas about motion.

3. he generalized the law of uniformly accelerated motion from the experiment of rolling brass balls down a groove on a inclined plane. Two equations of the law are: d=v*t d=1/2at*t

4. he made a telescope himself. He could see objects 9 times larger with the aid of it. Using the telescope, he observed sunspots, discovered four satellites of Jupiter, sketched the surface of moon of different phases, and proved the phases of Venus.

Kepler suffered from all kinds of diseases when he was young. He was very interested in science.

1. he made lots of scientific drawings of human eyeballs. He thought the lens of human eye worked the same way as the curved lenses of eyeglasses. They brought images in focus.

2. he tried to explain why all snowflakes had six corners, but because of the limit of chemistry at that time, he did get to the bottom of it.

3. he believed that earth and other planets revolve around the sun, and that a force from the sun accounts for the planets’ motion. The farther a planet is from the sun, the weaker the force is.

4. he came up with kepler’s laws of planetary motion.

i. each planet travels around the sun in a path that is an ellipse. The sun is off-center inside the ellipse.

ii. The speed of a planet’s orbit depends on its distance from the sun: closer is faster, and father is slower. A planet sweeps out equal areas of its ellipse in equal intervals of time.

iii. The farther a planet is from the sun, the longer it will take to go around the sun, and the longer its year will last.

Descartes was a brilliant philosopher and mathematician.

1. his idea of how to study science shown in his book discourse on the method of rightly conducting the reason and seeking the truth in the sciences is that the way to solve a difficult problem is to break the problem into several parts and deal with each of these parts separately.

2. he invented three dimension coordinates. He picked up three representative lines, one n-s, one e-w, one u-d and marked them with numbers. He links algebra and geometry.

3. he pondered that the universe is filled with invisible matter that swirls in vortices that keep the stars and planets on curved paths.

All of the scientists before Newton had a deep influence on Newton. He studied the work of there scientists and came up with world-shaking achievements:

1. he obtained an implication from the apple falling on his head and achieved the law of universal gravitation.

2. he invented calculus.

3. he was the first man who thought that light was made up of corpuscle and that white was the combination of seven colors.

4. he understood the law of motion:

i. objects tend to stay at rest or move in a straight line at a constant speed unless acted upon by an outside force.

ii. The force acting on a body is directly proportional to, and in the same direction as, its acceleration.

iii. For every action there is an equal and opposite reaction.

5. he proved mathematically that planetary orbits are elliptical.

The development of chemistry

1. Aristotle thought everything on earth was made from four elements which are earth, air, fire, and water.

2. geber kept trying to transmute matter. By distilling vinegar, geber got strong, pure samples of acid which could cause chemical changes.

3. andreas libau wrote a textbook which gave clear direction for preparing strong acids, such as hydrochloric acid, sulfuric acid, and nitric acid.

4. some alchemists who were seeking for gold and the fountain of youth were serious workers. Their experiments in the open air helped chemistry become science.

5. i. boyle used the chemical method of the flame test. He found that metals burn with flames of different colors. Lead is blue, sodium is orange-yellow, copper is bright green, and calcium is red-orange.

ii. he was an expert on assaying. He could tell silver from gold by using a strong acid.

iii. he defined elements as basic substance that can’t be separated into anything else. Elements can be combined to make compounds. Compounds can be divided into elements.

iv. he had a law that the volume of a gas at a constant temperature is inversely proportional to the pressure put on it.

6. jeseph black understood that air is actually a mixture of gases.

7. i. karl scheele discovered that air contains oxygen, carbon dioxide, and nitrogen.

ii. he discovered eight elements.

iii. he found a way to make phosphorus.

8. priest discovered a clue that plants and animals exist in a chemical balance, which keeps the earth’s atmosphere breathable.

9. i. Henry Cavendish found that carbon dioxide is 1.5 times heavier than air.

ii. he discovered that water is a compound of hydrogen and oxygen.

10. Fahrenheit, Celsius, and Kelvin invented thermometers which had different scales.

11.lavoisier is the father of chemistry:

i. he realized that mass of substances is never lost during chemical reaction. Scientist call that a conservation law.

ii. He found that combustion is a chemical reaction between two or more substances that gives off heat and light.

iii. he found 33 elements although not all of them were right.

12. i. dalton came to believe that all matter, consists of atoms. He took a big leap of mind by hypothesizing that it is the weight of its atoms that makes one element different from another.

ii. he said that atoms could neither be created nor destroyed and that chemical reactions were just rearrangements of atoms.

iv. he knew that if he weighed equal amounts of an elements and hydrogen and got the ratio of their weight. He could tell how an atom of the element was compared to an atom of hydrogen.

13. i. avogadro figured out that most gases were made up of particles containing two or more atoms held in a tight embrace.

ii. he came up with a law that is equal volumes of gas at the same temperature and pressure, contain an equal number of particles.

14. loschmidt worked avogadro’s number out in a series of experiments. Avogadro’s number shows how many molecules are in 22.4 liters of gas at a specific temperature.

15. i. kekule noted that carbon atoms tend to unite with other atoms in a ration of one to four.

ii. he said that carbon not only forms atomic chains, but also links into rings of atoms.

16. mendeleyev put atoms in order and created periodic table.

The evolution of physics

1. i. Daniel Bernoulli came up with a famous principle which is the pressure in a fluid varies inversely with its speed squared.

ii. he made a creative conjecture that gas are made up of a vast number of tiny particles which are in random and constant motion.

iii. he knew that heating the gas makes its atoms and molecules move faster.

2. du chatelet realized that the formula for energy is actually e=mv*v

3. carvendish built a precise torsion balance and measured the gravitational attraction.

4. i. franklin planed an experiment with a kite and a key and found out that lightning is actually electricity.

ii. he designed metal rods that can carry the electric charges in lightning safely to the ground.

5. i. faraday believed that electricity and magnetism are linked together as a force, and they travel in fields.

ii. he had new ideas about light which is light is electro-magnetic radiation, and it travels as vibrations in fields.

iii. he made the first electricity generator.

v. he designed the first electrical transformer to reduce high voltage current.

6. i. Maxwell said that light is electromagnetic and it travel as undulations (wavelike movement).

ii. he put forward that an electromagnetic wave is made up of waves that are at right angles to each other. One is electric field. The other is the magnetic field.

iii. he understood that different electromagnetic waves have different wave lengths.

iv. his four equations confirmed that electromagnetic rays travel at the same speed.

7 boltzmann figured out that heat is moving atoms and molecules. He came up with a formula to measure the speeds of molecules in a gas.

8. scientists came up with the first law of thermodynamics which is energy can be changed from one form to another, but it can’t be used up.

9.scientists came up with the second law of thermodynamics which is energy spreads out if it can, and it is always transmitted from hot to cold.

10. becquerel demonstrated that the x-ray from uranium is created inside the uranium atoms.