The Mayor Finding in the Physics History

Irmary Ortiz Carlo 

          If you ask to different physicians the same question: Which was the mayor finding in the physics history? Everybody will give you a different answer. Everyone has a different point of view of what was the best contribution of the physics to the science.  But a lot of scientists and physicians think that the best finding in the physics history was the Universal Law of Gravitation, of Isaac Newton. In 1687, Sir Isaac Newton in his work Philosophiae Naturalis Principia Mathematica formulated the three principles of the movement, and the fourth, The Universal Law of Gravitation, that transformed the physical world completely. All the phenomena could be seen in a mechanical way. This law states that all the objects are attracted with others with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance that separates its centers. When putting under a single mathematical law the more important physical phenomena of the observable universe, Newton demonstrated that the terrestrial physics and the celestial physics are a same thing. The gravitation concept obtained of a single blow:

Reveal the physical meaning of the three laws of Kepler about the planetary movement.

Solve the intricate problem of the origin of the tides.

Give to account of the peculiar and inexplicable observation of Galileo Galilei of which the movement of an object in free fall is independent of its weight.

        Newton compares the centripetal acceleration of the Moon, with the gravity acceleration. In the physics previous to Newton, an apple falls vertically towards the Earth in a rectilinear trajectory, whereas the Moon describes an almost circular orbit, which is a closed trajectory.  How these two categories of movements can be related?  If the apple that fell vertically is pushed by the force of the air, its trajectory no longer will be rectilinear but the arc of one curve. For example a projectile shot from a tube describes a parabolic trajectory as it was observed in the century XVII in which Newton lived. The conceptual jump that carried out Newton was the one to imagine that the projectiles could be shot from the stop of a mountain describing elliptical trajectories (being the parabola an approach of the ellipse). Therefore, the apple and the Moon are falling. The difference is that the Moon has a movement of permanent fall, whereas the apple hits the Earth surface. A same cause produces, therefore, the movements of the celestial and terrestrial bodies.

    Maybe, it can be hard to choose between all the fantastic findings that the physics history has. But the reality is that the Newton’s Universal Law of Gravitation changes the physics history forever.  

 

Bibliography:

http://www.sc.ehu.es/sbweb/fisica/celeste/kepler4/kepler4.html

Hydrogen in cars: another alternative of energy

Bethlyemid Guzman Ocasio

      Hydrogen is a chemical element that at standard temperature and pressure is a colorless, odorless, non-metallic, tasteless and highly flammable diatomic gas. It is the most abundant element on the Earth. It can be produced industrially mainly from hydrocarbons such as methane or also may be produced from water by electrolysis, at substantially greater cost than production from natural gas.

      A hydrogen vehicle uses hydrogen as its main fuel for motive power. The term may refer to an automobile or any other vehicle that uses hydrogen as fuel, such as an aircraft. The power plants of these vehicles convert the chemical energy produced by the hydrogen into mechanical energy. There are two types of mechanical energy: combustion or electrochemical conversion using a fuel-cell.

      There are many types of transportation that already run on hydrogen at a great expense. NASA uses hydrogen to launch space shuttles. There is a toy model car that uses a solar energy, storing hydrogen and oxygen gas, using a regenerative fuel cell, which can convert the fuel back to water and release the solar energy. Many companies are still researching the feasibility of building hydrogen cars, and most of them have started to develop them, although most of them are still on test stage.

      A hydrogen internal combustion vehicle is different from a fuel cell vehicle. The hydrogen internal combustion vehicle is a slightly modified version of the traditional gasoline vehicle. The hydrogen engines burn fuel in the same manner that gasoline engines do. But the most effective use of hydrogen fuel is on a fuel cell vehicle because hydrogen reacts with oxygen inside the fuel cell, which produces electricity to run the motor of the vehicle.

      The development of such technology would mean a great impact on our economy. It may be expensive at the beginning of the development until new discoveries are made but the impact on the long run would be great. If the technology can be made in such a way that, when hydrogen reacts, would only produce water, that would mean a great downsize of the contamination in the planet. Using hydrogen as an alternative source of energy can give us an option and hope of another type of fuel and we would not have to depend on petroleum or other sources of fuel that keep coming to an end over each passing year.

      There are actually people who are making modifications to their cars so they can run both on hydrogen and gasoline. With $600 dollars more or less for the modification, what they are actually saving on fuel each year is a whole lot more. On top of that, we would be minimisizing the use of petroleum.

      The hydrogen technology not only opens up it usage on cars but it can be a subtle change on our dependence of non-renewable energy. It can stimulate the development of other types of renewable energy like solar, hydropower or wind power; even though there are people who use them it is a minority. Eco-friendly energy, if developed fully, may help to maintain a better place for all of us to live.

http://en.wikipedia.org/wiki/Hydrogen_vehicle

http://en.wikipedia.org/wiki/Hydrogen_internal_combustion_engine_vehicle