Law Of Conservation of Energy

Energy conservation laws define the essence of life and Universe. In this write up, a simple definition of law of conservation of energy has been provided.
One of the most profound laws of Universe is the law of conservation of energy that always holds true. There is a fact, or if you wish, a law, governing all natural phenomena that are known to date. There is no known exception to this law—it is exact so far as we know. The law is called theconservation of energy. It states that there is a certain quantity, which we call energy, that does not change in manifold changes which nature undergoes. That is a most abstract idea, because it is a mathematical principle; it says that there is a numerical quantity which does not change when something happens. It is not a description of a mechanism, or anything concrete; it is just a strange fact that we can calculate some number and when we finish watching nature go through her tricks and calculate the number again, it is the same."- Richard Feynman, Nobel Physics Laureate and Celebrated Physicist.

The concept of law of conservation of energy has been beautifully put forth by one of the most renowned physicists of the late century, Richard Feynman, in the above lines. In fact, describing the concept of energy is a fairly simple task, as it is an integral part of Universe, an inseparable part of life. Without energy, there is no existence of Universe. Energy is manifested in every walk of life. Be it the supersonic jet planes or merely riding a bicycle, energy is manifested in every act we do. Although, there are different forms of energy, there is one Universal law that applies to all of them, that is, the law of conservation of energy.

What is the Law of Conservation of Energy

The development of numerous theories related to "energy" occurred in the 19th century when legends like Lord Kelvin, Rudolf Clausius and Walther Nernst conceptualized numerous thermodynamics laws that triggered the rapid acceptance of energy to explain numerous chemical processes. Moreover, energy was also established as a mathematically entity after Clausius formulated the law of Entropy. So what does the energy conservation law state? A simple law of conservation of energy definition would be that energy can neither be created nor be destroyed but it can be transformed from one body to the other. This is perhaps the simplest definition of energy conservation that we were taught in our school physics classes.

In higher physics, understanding the law of conservation of energy is a bit challenging as there are numerous other fundamental laws that govern the entire energy conservation law. Most notably, the Noether's theorem that is a basis of modern theoretical physics. Discussing the energy conservation law in the light of higher physics is not possible in the limitations of this article, however, the basic essence of conservation law remains the same, that is energy can only be transformed from one body to the other, but it can't be destroyed.

For instance, the gravitational potential energy stored in a dam is converted into kinetic energy, in the form of moving water or chemical energy in a battery is converted into electrical energy. All these are perfect examples of conversion of one form of energy into the other.

Even mechanical energy, that is the kinetic and potential energy, always remain conserved in an isolated system. The law of conservation of mechanical energy is based on similar lines, just like the energy conservation laws. Even mass is related to energy and this revolutionary theory was put forward by the genius Albert Einstein, who gave the mass energy equivalence theorem or E = mc².

Is there any specific law of conservation of energy equation? Well, depending on the system we're considering, there are numerous energy conservation equations. In mechanics, thermodynamics, relativistic mechanics, we've different energy equations, which requires one to define the kinetic and potential energies of the respective systems. The most generalized form of energy conservation equation is,

E = T + V, where T = Kinetic Energy, V = Potential Energy and E = Total energy of the system.

Although, in higher physics, there are numerous conditions on law of conservation of energy. In essence, the fact is that energy conservation is a universal law and it amazes physicists about the precision of nature's law. They're true everywhere and does not change over time.

Ionization Potential

What is ionization potential? Why does ionization potential affect the reactivity of any atom? Read to find all the answers. . .
All of theoretical chemistry related to atomic and molecular reactions is quantum physics, which studies the energy changes associated with electrons and provides a system for probability calculations of atomic and molecular orbitals. One of the important concepts associated with atomic physics is the ionization potential of an atom. The aim of this article is to provide a clear explanation of what is ionization potential of an atom.

Before we go ahead and talk about ionization potential, let me brush up some of the basics of atomic structure. An atom consists of a central nucleus containing positively charged protons and neutrons, which is surrounded by electrons revolving around it in orbitals with specific energy levels. The electrons are bound to the atomic nucleus, because of the electromagnetic force of attraction between the electrons and protons inside the nucleus.

To break free from the attractive force of the atomic nucleus, an electron requires energy which may be supplied from external sources. For every atom, the energy levels for each atomic orbital are different. With that background, we are ready for a discussion of what is ionization potential.

What is Ionization Potential?

The ionization potential or ionization energy is defined as the total amount of energy required to free an electron revolving in the outermost shell of any atom. Alternatively, chemists also define it as the total energy required to liberate one mole of electrons, from one mole of a particular atom. The units used for measurement of ionization potential are more than one.

In physics, we prefer using electron volts (eV) per atom as a unit for ionization potential, while in chemistry, the ionization potential is measure in terms of kJ / mol (Kilojoules per Mole). For example, the ionization potential of Hydrogen is 13.5984 eV. The lower the ionization energy, higher is the tendency of an atom to become a reducing agent and more reactive it is. On the other hand, higher is the ionization energy, higher is the tendency to become an oxidizing agent and less reactive it is.

What is the Ionization Potential Equation?

To be able to measure the ionization potential for any atom, one must solve the Schrodinger equation from quantum physics, to calculate the energy levels of that atom. A complete analytical solution for any atom, other than Hydrogen is not possible, an estimate of the ionization potential energy can be made on the basis of an approximate model. The following equation can be used to estimate the ionization potential energy of an electron in any shell of the atom.

Ionization Potential (eV) = 13.6 eV x (Z² / n²)

where Z is the atomic number of the atom and n is the orbital number. This formula can only provide you with an approximate value. A more precise value can only be obtained from experiments.

The energy required to liberate one electron from an atom's outer shell of electrons is known as first ionization potential, while the energy required to liberate the second one is known as the second ionization potential. Second ionization potentials are always higher than first ionization potentials. That is because, more you take away the electrons from its outermost shells, more tightly does an atom hold the rest, which are left.

As we saw before, the key point to understand is that higher the ionization potential of an atom, greater will be the energy required to remove an electron from inner level orbitals of the atom. In conclusion remember that atoms with low ionization potential lose electrons easily and are hence good reducing agents. On the other hand, atoms with high ionization potentials are more likely to be oxidizing agents. As an exercise, take a look at the ionization potential table for all elements and guess which elements are likely to be reducing or oxidizing agents. Hope this article has left no doubt in your mind about what is the ionization potential of an atom.

Piezoelectric Effect

In physics, piezoelectric effect is the vital link between the study of static and moving electric charges - electrostatics and the science of dynamics, motion and speed - mechanics. More information about the same has been presented below.
In the world of physics, studying analogies between laws of electrostatics and mechanics is fascinating and they point to a very basic understanding of this Universe, and there is a deeper science behind the mysterious order of this Universe. Piezoelectric effect is yet another phenomena that describes a beautiful analogy between stress or mechanical strain and electrical voltage.
What is Piezoelectric Effect?

It was owing to the efforts of Jacques Curie and Pierre Curie, in 1880 that the concept of piezoelectricity came into existence. These physicists discovered that there are certain crystals that become electrically polarized when stress or mechanical strain is applied on them. So all elements of mechanics like stress, strain, compression and elongation can produce voltages in some specific crystals. It was established by Jacques and Pierre that when mechanical force was applied upon crystals like tourmaline, topaz, quartz, Rochelle salt and cane sugar, it lead to the production of alternate electric charges on its opposite faces and subsequently it could be used to generate electrical voltage.

The crystals that showed the presence of this phenomena were named as piezoelectric materials or crystals. So, when stress is applied on a piezoelectric crystal, it will lead to voltage generation across its surface. These crystals can be best understood as capacitors with some voltage applied on them. The voltage generated is certainly not very large, but it can be amplified to great extent by using amplifiers.

The reverse piezoelectric effect was also found to be true in researches during the later years, after the discovery of peizoelectric phenomena. As per reverse peizoelectric effect, when external voltage is applied on piezoelectric crystals, they will show variance in shape and size, up to a very small extent. The electricity that is produced in the process of piezoelectric effect is known as piezoelectric.

Applications of Piezoelectric Effect

It becomes fairly easy to understand the laws of Physics once we're able to observe their applications in daily life. There are many areas where piezoelectric phenomena is used extensively. Piezoelectric effect only occurs in non conducting materials and broadly stated, peizoelectric materials are bifurcated into two groups, crystals and ceramics.

• Electric cigarette lighter uses piezoelectric phenomena for lighting the cigarette. When we press the button of an electric cigarette lighter, a spring loaded hammer strikes an in-built peizoelectric material and produces a very high voltage, thereby igniting the gas.
• Many stoves and grills come with in-built peizoelectric crystals.
• Piezoelectric transformers (quite different from conventional transformers) have become one of the most significant sources of high voltage generation.
• Piezoelectric sensors have become popular in acoustic guitars and other equipment. Variations in pressure, in the form of sound, is easily detected by using peizoelectric sensors.
• In ultrasonic transducers (used for medical imaging), the concept of peizoelectric effect is used.
• Piezoelectric crystals are also used in detection and generation of sound waves.
• Sonochemistry, industrial processing and several branches of engineering physics use peizoelectric crystals.
• In actuators, peizoelectric ceramics are used as the width and electricity produced by these crystals can be very accurately measured.
• Loudspeakers, peizoelectric motors, ink jet printers are some other devices where peizoelectric effect is used.
• In microscopes, especially the atomic force microscopes and scanning tunneling microscopes, the phenomena of peizoelectric effect is used.

So did you get piezoelectric effect definition? The above applications are just a glimpse of the peizoelectric effect. In bones too, this phenomena is observed as bones, DNA and other biological matter inherently have the ability to accumulate charges! As studies in electromagnetism and mechanics are becoming more advanced, several other fields that employ peizoelectric effect are developing rapidly.

Coherent Light (2)

Linac Coherent Light Source
The linac coherent light source (LCLS) produces pulses of X-rays more than a billion times brighter than the most powerful existing sources, the so-called synchrotron sources which are also based on large electron accelerators. The ultrafast X-ray pulses are used much like flashes from a high-speed strobe light, enabling scientists to take stop-motion pictures of atoms and molecules in motion, shedding light on the fundamental processes of physics, technology, and life itself. 
(Source: Stanford University)

Xenon Light
Xenon is a colorless, heavy element with atomic number 54. Xenon gas is used for light emitting devices known as Xenon light. Some of the uses of Xenon light are

• It is used in photographic flashes, stroboscopic lamps and solar simulators.
• Xenon light is also used as in arc lamps and high intensity discharge headlights.( Remember the advert of the car mentioning its xenon headlights)
• It has been used for anaesthetic purposes, although it is expensive.
• Xenon light also finds its use in plasma display for televisions.

Coherent light is useful in so many ways that scientists all over the world are keenly researching its other uses like treatment in cancer etc. Although it is a vast topic, I hope this information would be useful for you to understand what is coherent light and some of the other basic things about coherent light.

What is Plasma in Physics

In physics, to put the definition very simply, plasma is a fourth state of matter that comes after solid, liquid and gases. The state of plasma is achieved when gas or gases are heated to the extent that the atoms of the gas lose all electors. The resultant quasi-gas is a collection of nuclei and electrons that are free. The nuclei which has lost all the electrons are deemed to be ions, that is, they are electrically charged, to a substantial extent. The entire collection is thus, electrically charged and conductive. The basic process that takes place in formation of plasma is quite simple. When heated, energy gets pumped into the gas. This causes that gas to disassociate itself from its molecules and take the form of atoms, which further loose their negatively charged electrons. The atoms themselves retain positive charge and are thus, deemed to be positive ions. 

Plasma, thus, cannot occur naturally, i.e, in free environment on earth. It needs a controlled environment of electromagnetic field to survive without reacting. Stars, which are existent in space, are the best example of plasma. The vacuum of space prevents them from reacting. Scientists have laid down certain parameters that define plasma. These parameters include, the approximation of ions and electrons, the frequency and volume of iterations, size, lifetime, density, temperature and magnetic fields are the constituents of the definition.

The question 'what is plasma used for', is quite evident. The naturally existing plasma is in stars or lightning. Artificially produced plasma is included in applications such as neon signs and plasma display television. Coincidentally, Irving Langmuir in 1928, named the phenomenon, 'plasma' owing to the fact that it strongly resembled blood plasma. For more leads on plasma as a substance, you may have a look at some of its applications and how they work:

Italy To Build Accelerator/Collider With US Parts

Italy To Build Accelerator/Collider With US Parts

As further signs that the US truly is going out of particle collider experiments, an agreement has been reached for Italy's SuperB to be built with parts from the now decomissioned PEP-II accelerator at SLAC.

Petronzio says he hopes that the Italian ministry will agree to a construction schedule early next year and that SuperB will start taking data around 2016. The construction of SuperB is contingent on the U.S. Department of Energy (DOE) contributing the machinery of PEP-II, which would be worth more than €100 million. However, David MacFarlane, SLAC's associate director for particle physics and particle astrophysics, says the lab and the agency are onboard with the project: "Both DOE and the laboratory are fully committed to supplying the equipment requested."

Whether U.S. physicists will be able to fully participate in the Italy project is another matter. To support such participation, DOE officials will have to find some room in the agency's already tight $810 million particle physics budget. But David Hitlin, a particle physicist at the California Institute of Technology in Pasadena who has been involved in the project since its inception, says that SuperB presents DOE with a scientific bargain. "DOE can be a major player in the project for a relatively small amount of money by leveraging the in-kind contribution" of the equipment, he says. For the moment, Hitlin says he's just happy that the project seems to be coming to fruition: "It's nice that it's real."

THe US is losing grounds on high energy physics experiments. And no one seems to be concerned about it. Might as well give these equipment to those who appreciate their importance. So Merry Christmas, Italy!