**Physics and Mechanical Universe 2**

**The mechanical universe**

Performed by the California Institute of Technology The Corporation for Community College. It takes a tour of the different fields of physics: electricity, magnetism, mechanics, etc.

**Lesson 21, The three laws of Kepler.**

The “three laws of Kepler,” the wandering mathematician, described the movement of the celestial bodies with an accuracy that had never been given before. However, the planets kept moving in the orbits drawn by the ancient Greek mathematicians: the conical section called an ellipse. Pedagogical objectives: Know the historical significance of the “Kepler laws”. List precisely the “Kepler laws”. Identify the relationship between conic sections and the “Kepler laws”. Define eccentricity and the formula of a conic section in polar coordinates.

**Lesson 22, Kepler’s problem.**

The task of deducing the 3″Kepler Laws” from the “Newton’s Law of Universal Gravitation” is thought because of the “Kepler drawback.” His solution is one of the great achievements of Western thought. Pedagogical objectives: describe the value of velocity in polar coordinates; state the angular momentum formula in polar coordinates; verbalize the “Kepler problem”; interpret how “Newton’s laws” give a solution to “Kepler’s problem.”

**Lesson 23, Energy and eccentricity.**

The precise orbit of any celestial body (planet, asteroid or comet) is established by the principles of conservation of energy and angular momentum. Eccentricity, which determines the shape of an orbit, is intimately linked to energy and the angular momentum of the celestial body. Pedagogical objectives: interpret the relationship between energy and eccentricity; identify the orbits by eccentricity; know the construct of effective potential however|and the way} it relates to the planetary movement; justify how initial conditions have an effect on the orbit of a planet, estraterrestrial body or satellite.

**Lesson 24, Navigate through space.**

How to get there. Trips to other planets demand huge amounts of energy. However, the amount of energy spent can be minimized by using the same principles that guide the planets around the Solar System. Pedagogical objectives: explain how the force of gravity is used in interplanetary travel; comment on the relationship of launch opportunities to inner and outer planets; calculate the periods and speeds of transfer orbits between planets; justify the use of transfer orbits; describe the influence of gravitational attraction on a satellite and on the planet.

**Lesson 25, From Kepler to Einstein.**

The planets in orbit, the ebb and flow of the tides, the body that falls with an accelerated movement, all these phenomena are a consequence of the “Law of Gravity”. This leads us to the “General Theory of Einstein’s Relativity” and the discovery of black holes. Pedagogical Objectives: to interpret the implications of the “third law of Kepler” in planetary calculations; know the meaning of the center of mass of the Sun-Earth system; explain the causes of the tides; differentiate between inert mass and gravitational mass; Qualitatively identify the concept of the black hole.

**Lesson 26, The harmony of the universe.**

The music of the spheres. Pedagogical objectives: indicate a brief historical report of the “Kepler problem”; differentiate the conceptions of the world of Physics from: Aristotle, Galileo, Kepler and Newton; explain why they call mathematics the language of physics; know the meaning of conservation principles; explain why some would say that mechanics is the basis of all western knowledge.

**Lesson 27, Beyond the mechanical universe.**

The investigation of “Beyond the Mechanical Universe” begins with suggestive questions. This advance as a presentation introduces us to the world of Electricity and Magnetism, reaches the discoveries of Relativity and Quantum Mechanics in the twentieth century. The brilliant ideas of Faraday, Ampère, Maxwell, Einstein, Heisenberg, and Shrödinger add to the “Newton Mechanical Universe”.

**Lesson 28, Static electricity.**

To understand the nature of matter, one must first understand electricity, and to understand the nature of electricity one must first understand matter. The eighteenth-century electricians did not understand either one or the other, but they knew what aroused public interest and how to set up an electrifying show. The “Coulomb’s law” and the principles of static electricity. Pedagogical objectives: identify and comment on electrical phenomena; explain electrification by rubbing, induction and contact; interpret the “Coulomb’s law” and use it to find the force exerted by a point load on another; difference between insulator and conductor; explain the ACR, attraction, contact and repulsion; Describe the principles of an electrostatic generator.

**Lesson 29, The Electric Field**

Pedagogical objectives: draw lines of forces from simple charging systems and obtain information on the direction and strength of an electric field, based on such a diagram; calculate the electric field generated by point charges and continuous charge distributions, for simple cases; define the concept of flow and the law “1/ r2”; interpret the “Gaussian Law” and use it to find the electric field produced by several symmetric charge distributions; recognize that a load distribution in symmetric spherical armatures produces a null electric field within the armor that is equal to that produced by a point charge at the geometric center of the armor; explain why the electric field within a conductor is null.

Read more at:

https://en.wikipedia.org/wiki/Electric_field

**Lesson 30, Capacity and potential.**

Benjamin Franklin, the great American scientist of the eighteenth century, who later devoted himself to politics, was the first to propose the “Leyden bottle.” He baptized with names of negative and positive to the electric charge, and invented the parallel plate capacitor. Electrical potential, potential of charged conductors, equipotential surfaces and capacity. Pedagogical objectives: draw an outline of the equipotential surfaces given the electric field of a region; distinguish between electric potential and electric potential energy; define capacity and calculate the capacity of a parallel sheet capacitor; interpret the energy density of an electric field and discuss the energy concept of the electrostatic field.

**Lesson 31, Voltage, energy and strength.**

In a world of electric charges and currents, fields, forces and electrical voltages, what really happens? When is electricity dangerous, harmless, spectacular or useful? The electric potential and its great; the electrical potentials in atoms and metals; electric power and why a spark jumps. Pedagogical objectives: define the concept of great; interpret the graphic relationship between lines of force and equipotential surfaces in the electric field; know the average magnitudes of voltages and forces in the matter; explain the operation of a lightning rod; define the unit of electrical energy, volt, and its conversion to joules; explain why sparks occur

**Lesson 32, The Electric Battery.**

Electricity went from being a mere curiosity to constituting a fundamental concern of science and technology in the 19th century, when Alejandro Volta invented the electric battery. The batteries use as a source of the internal properties of different metals to produce electrical energy. Pedagogical objectives: interpret the internal and external potentials of metals; Explain the work of the process inside an electric battery.

**Lesson 33, Electrical circuits.**

The design and analysis of the flow of currents in circuits and series and in parallel, with resistors and capacitors, depends not solely on the renowned “Laws of Ohm and. Pedagogical objectives: define the concepts of electric current and current intensity; interpret the “Ohm’s Law” and distinguish between it and the definition of resistance; the general relationship between potential difference, current intensity and power; identify elements of series and parallel circuits; apply Kirchhoff’s rules and use them to analyze elementary DC circuits;

**Lesson 34, Magnetism.**

William Gilbert, personal Dr. by the designation of Queen of {england} of England, discovered that the planet behaves sort of a big magnet. Magnetism is a phenomenon, the behavior of magnetic materials, and the movement of charged particles in a magnetic field. Pedagogical objectives: calculate the magnetic force on an electric conductor and on a moving load within a magnetic field; explain the concept of “domains” in ferromagnetic materials; define the concept of magnetic flux and comment on the meaning that the net magnetic flux outside a closed surface is zero; calculate the magnetic moment of a loop with a current intensity and the torque exerted on the loop by a magnetic field; recognize the magnetism of the Earth.

**Lesson 35, Magnetic Field**

It can be thought that every magnetic field is produced by an electric current. The relationship between current intensity and the magnetic field it produces is, from the geometric point of view, very particular and its assimilation has some difficulty. The “Law of Biot and Sarvart”, the force between electric currents and the “Law of Ampère”. Pedagogical objectives: interpret the “Biot and Servant Law” and use it to calculate the magnetic field created by a current in a rectilinear conductor and by a current of a circular loop; define the “Law of Ampère” and comment on its uses and limitations; calculate the forces between currents; list the different units of field strength; recognize that the magnetic field cannot produce work.

**Lesson 36, Vector and hydrodynamic fields.**

At first glance, replacing the old idea of distance action with the new conception of force field seems to be an exercise in semantics, but it is not, because the fields have their own definition properties, suitable for scientific study. Electric fields, for example, are different in their form from magnetic fields, and both can be better understood by their analogy with fluid flow fields. Pedagogical objectives: define the concepts of flow and circulation; relate electric and magnetic flux and circulation with fluid velocity fields; Explain the difference between energies and forces for vector fields.

**Lesson 37, Electromagnetic Induction.**

The discovery of electromagnetic induction, by Miguel Faraday and Joseph Henry, in 1831, was one of the most important findings of the 19th century, not only from the scientific point of view, but also from the technological point of view, because it is the means by which Almost all electrical power is currently generated. Pedagogical Objectives: to interpret the “Faraday Law” and use it to find the electromagnetic force induced by a changing magnetic flux; state the “Lenz Law” and use it to find the direction of the induced current in different applications of the “Faraday Law”; define self-induction and mutual induction; identify the energy stored in a magnetic field and the density of magnetic energy; apply the “Kirchhoff Laws”

**Lesson 38, Alternating currents.**

Electromagnetic induction makes generating alternating current something easy and natural. The use of transformers makes it possible to distribute alternating current over long distances. AC circuits obey a differential equation identical to the resonance of a harmonic oscillator. Pedagogical objectives: define the SMR current and relate it to the maximum current of an alternating current circuit; indicate the phase relationship between voltage and current in the elements of an RLC circuit; comment on the relationship between an RLC circuit and a harmonic oscillator; describe what is a low and high voltage electrical transformer; analyze the relationship between voltage and power transmission; determine the resonance conditions of an RLC circuit

**Lesson 39, Maxwell’s equations.**

The “Displacement current” James Clerk Maxwell discovers the, which was just what was needed to produce electromagnetic waves called (among other things) light. Pedagogical objectives: interpret the “Maxwell equations” and discuss the experimental basis of each of them; define, according to Maxwell,”displacement current” and comment on its meaning; conclude that The equations of Maxwell’s expose that light-weight is associate degree radiation; state the expression of the speed of associate degree magnetic force wave in terms of magnetic and electrical current.

**Lesson 40, Optics.**

The “Maxwell Theory” says that electromagnetic waves of any wavelength, from radio waves to gamma rays, including visible light, constitute basically the same phenomenon. Many of the properties of light are really properties of a wave, such as reflection, refraction, and diffraction. Normal light-weight is wont to see things on a personality scale, X-rays to “see” things on the associate atomic scale. education objectives:comment on the nature and properties of the different parts of the electromagnetic spectrum; interpret the Laws of “Reflection” and “Snell Refraction”, and relate them to the properties of waves; explain what the interference and diffraction of the waves consist of; analyze how we can “see” atoms.