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PI-RADOS | Another Day In The Lab. Representación de los primeros 1000 decimales de pi usando Circos, un software de genómica. (Autores: Cristian Ilies Vasile y Martin Krzywinski). Hoy es el día π. A muchos esto no os dirá nada, pero yo voy a celebrarlo igualmente con una entrada por dos buenas razones. La primera es que es mi número favorito, soy un πrado. La enciclopedia Sopena. Salí decidido de mi habitación hacia la fuente de conocimiento más profunda de mi casa: la enciclopedia. Π es la razón constante entre la longitud de cualquier circunferencia y su diámetro. Debí buscar también lo que significa razón, que por suerte estaba en el mismo volumen =).

Pi explicado gráficamente. Eso ya me pareció algo realmente sorprendente. Los números irracionales tienen infinitos decimales y no hay un patrón en ellos, así que el valor exacto de π no se podrá saber nunca: por eso la mejor forma de definirlo es una letra. El problema de Basilea Leonard Euler (1707-1783) 1 + 1/4 + 1/9 + 1/16 + 1/25 + 1/36 +… = π2/6 Sí. ¿Os suena? Voilà. Selected Tesla Writings -- Table of Contents. A New System of Alternate Current Motors and Transformers, AIEE Address, May 16, 1888 Phenomena of Alternating Currents of Very High Frequency, Electrical World, Feb. 21, 1891 The Tesla Effects With High Frequency and High Potential Currents, Introduction.

--The Scope of the Tesla Lectures. On the Dissipation of the Electrical Energy of the Hertz Resonator, Electrical Engineer, Dec. 21, 1892 Tesla's Oscillator and Other Inventions, Century Illustrated Magazine, April 1895 Earth Electricity to Kill Monopoly, The World Sunday Magazine — March 8, 1896 On Electricity, Electrical Review, January 27, 1897 High Frequency Oscillators for Electro-therapeutic and Other Purposes, Electrical Engineer, November 17, 1898 Plans to Dispense With Artillery of the Present Type, The Sun, New York, November 21, 1898 Tesla Describes His Efforts in Various Fields of Work, Electrical Review - New York, November 30, 1898 On Current Interrupters, Electrical Review, March 15, 1899 Mr.

Dr. Dr. "The Problem of Increasing Human Energy" by Nikola Tesla. DIAGRAM a. THE THREE WAYS OF INCREASING HUMAN ENERGY. Let, then, in diagram a, M represent the mass of man. This mass is impelled in one direction by a force f, which is resisted by another partly frictional and partly negative force R, acting in a direction exactly opposite, and retarding the movement of the mass. Such an antagonistic force is present in every movement and must be taken into consideration. The difference between these two forces is the effective force which imparts a velocity V to the mass M in the direction of the arrow on the line representing the force f.

In accordance with the preceding, the human energy will then be given by the product — MV2 = — MV x V, in which M is the total mass of man in the ordinary interpretation of the term "mass," and V is a certain hypothetical velocity, which, in the present state of science, we are unable exactly to define and determine. How to provide good and plentiful food is, therefore, a most important question of the day. Apuntes FyQ 1º Bachillerato. Física y Química 4º ESO. Pure mathematics. An illustration of the Banach–Tarski paradox, a famous result in pure mathematics. Although it is proven that it is possible to convert one sphere into two using nothing but cuts and rotations, the transformation involves objects that cannot exist in the physical world. Broadly speaking, pure mathematics is mathematics that studies entirely abstract concepts. This was a recognizable category of mathematical activity from the 19th century onwards,[1] at variance with the trend towards meeting the needs of navigation, astronomy, physics, economics, engineering, and so on.

Another view is that pure mathematics is not necessarily applied mathematics: it is possible to study abstract entities with respect to their intrinsic nature, and not be concerned with how they manifest in the real world.[2] Even though the pure and applied viewpoints are distinct philosophical positions, in practice there is much overlap in the activity of pure and applied mathematicians. History[edit] 19th century[edit] Materials science. Interdisciplinary field which deals with discovery and design of new materials, primarily of physical and chemical properties of solids The interdisciplinary field of materials science, also commonly termed materials science and engineering, is the design and discovery of new materials, particularly solids.

The intellectual origins of materials science stem from the Enlightenment, when researchers began to use analytical thinking from chemistry, physics, and engineering to understand ancient, phenomenological observations in metallurgy and mineralogy.[1][2] Materials science still incorporates elements of physics, chemistry, and engineering. As such, the field was long considered by academic institutions as a sub-field of these related fields.

Beginning in the 1940s, materials science began to be more widely recognized as a specific and distinct field of science and engineering, and major technical universities around the world created dedicated schools for its study. History[edit] [edit] Solid-state physics - Wikipedia. Digital Einstein Papers Home. String Theory for Kids (and Clever Adults) | String theory explained for kids, teens, and even adults. NASA in PMC. Vector Addition. A variety of mathematical operations can be performed with and upon vectors. One such operation is the addition of vectors. Two vectors can be added together to determine the result (or resultant). This process of adding two or more vectors has already been discussed in an earlier unit.

Recall in our discussion of Newton's laws of motion, that the net force experienced by an object was determined by computing the vector sum of all the individual forces acting upon that object. That is the net force was the result (or resultant) of adding up all the force vectors. During that unit, the rules for summing vectors (such as force vectors) were kept relatively simple.

Observe the following summations of two force vectors: These rules for summing vectors were applied to free-body diagrams in order to determine the net force (i.e., the vector sum of all the individual forces). The Pythagorean Theorem To see how the method works, consider the following problem: SCALE: 1 cm = 5 m SCALE: 1 cm = 5 m. Scalars and Vectors. Physics is a mathematical science. The underlying concepts and principles have a mathematical basis. Throughout the course of our study of physics, we will encounter a variety of concepts that have a mathematical basis associated with them. While our emphasis will often be upon the conceptual nature of physics, we will give considerable and persistent attention to its mathematical aspect. The motion of objects can be described by words. Even a person without a background in physics has a collection of words that can be used to describe moving objects. Words and phrases such as going fast, stopped, slowing down, speeding up, and turning provide a sufficient vocabulary for describing the motion of objects.

Scalars are quantities that are fully described by a magnitude (or numerical value) alone. The remainder of this lesson will focus on several examples of vector and scalar quantities (distance, displacement, speed, velocity, and acceleration). Check Your Understanding 1.