The Bohr model adopted Planck's quantum hypothesis and he proposed a model in which the electrons of an atom were assumed to orbit the nucleus but could only do so in a finite set of orbits. Planck's quantum hypothesis ( Planck's law ) is named after a German theoretical physicist Max Planck, who proposed it in 1900

Niel Bohr's Atomic Theory states that - an atom is like a planetary model where electrons were situated in discretely energized orbits. The atom would radiate a photon when an excited electron would jump down from a higher orbit to a lower orbit. The difference between the energies of those orbits would be equal to the energy of the photon Bohr model of the hydrogen atom attempts to plug in certain gaps as suggested by Rutherford's model by including ideas from the newly developing Quantum hypothesis. According to Rutherford's model, an atom has a central nucleus and electron/s revolve around it like the sun-planet system The Bohr Model is a planetary model in which the negatively charged electrons orbit a small, positively charged nucleus similar to the planets orbiting the sun (except that the orbits are not planar) * In atomic physics*, the Bohr model or Rutherford-Bohr model, presented by Niels Bohr and Ernest Rutherford in 1913, is a system consisting of a small, dense nucleus surrounded by orbiting electrons—similar to the structure of the Solar System, but with attraction provided by electrostatic forces in place of gravity

The Bohr model of the atom, a radical departure from earlier, classical descriptions, was the first that incorporated quantum theory and was the predecessor of wholly quantum-mechanical models. The Bohr model and all of its successors describe the properties of atomic electrons in terms of a set of allowed (possible) values. Atoms absorb or emit radiation only when the electrons abruptly jump between allowed, or stationary, states A) Bohr's Postulates. 1. An atom has a number of stable orbits in which an electron can reside without the emission of radiant energy. Each orbit corresponds, to a certain energy level. 2. An electron may jump spontaneously from one orbit (energy level E1. . ) to the other orbit (energy level E2. Származása, családja. Koppenhágában született 1885-ben szülei második gyermekeként (első fiaként).Apja, Christian Bohr 1886-tól a Koppenhágai Egyetem fiziológiaprofesszora volt, a Dán Királyi Tudományos és Irodalmi Akadémia tagja. Anyja, Ellen Adler (Ellen Adler Bohr) egy gazdag, bank- és parlamenti körökben prominensnek számító szefárd zsidó családból jött The Bohr atomic model (sometimes known as the Rutherford-Bohr atomic model) was a major milestone in the development of modern atomic theor

- Niels Bohr's 1913 model proposes quantized electrons to satisfy spectral data but without further support. Louis de Broglie (1924) made a highly significant.
- Bohr's Equation. Bohr Model of the hydrogen atom first proposed the planetary model, but later an assumption concerning the electrons was made. The assumption was the quantization of the structure of atoms. Bohr's proposed that electrons orbited the nucleus in specific orbits or shells with a fixed radius
- The Copenhagen interpretation is an expression of the meaning of quantum mechanics that was largely devised from 1925 to 1927 by Niels Bohr and Werner Heisenberg.It is one of the oldest of numerous proposed interpretations of quantum mechanics, and remains one of the most commonly taught.. According to the Copenhagen interpretation, material objects, on a microscopic level, generally do not.
- A Bohr-féle atommodell alapján értelmezhetők az atommag kibocsátási és elnyelési színképei. A Bohr-féle atommodell helyességét a H színkép vonalai bizonyították, ugyanis az ebben megjelenő színkép-vonalak energiája pontosan megegyezett a Bohr-féle atommodellből kiszámított atompályák energiakülönbségeivel

** Gli studi**. Bohr nacque a Copenaghen il 7 ottobre 1885.Suo padre, Christian Bohr, era un fisiologo danese di religione luterana, docente alla facoltà di Fisiologia all'Università di Copenaghen e scopritore di un comportamento dell'emoglobina detto effetto Bohr.Henrik Bohr, suo nonno paterno, fu insegnante e successivamente preside del Westenske Institut di Copenaghen Rutherford's model of an Atom was undoubtedly a breakthrough in Atomic studies. However, it wasn't completely correct. It needed slight modifications. These. De Broglie-hipotézis. Bővebben: De Broglie-hipotézis: Az 1920-as évekre a fizikusok rájöttek, hogy a Bohr-elmélet számos hiányosságot mutat: például hogyan lehet magyarázni, hogy csak bizonyos energiaszintek lehetségesek, vagy miért vannak egy elem minden atomjának ugyanazon tulajdonságai, annak ellenére, hogy egy atomban.

- Niels Henrik David Bohr (Danish: [ˈne̝ls ˈpoɐ̯ˀ]; 7 October 1885 - 18 November 1962) was a Danish physicist who made foundational contributions to understanding atomic structure and quantum theory, for which he received the Nobel Prize in Physics in 1922. Bohr was also a philosopher and a promoter of scientific research
- In 1913, Niels Bohr proposed a theory for the hydrogen atom based on quantum theory that energy is transferred only in certain well defined quantities. Electrons should move around the nucleus but only in prescribed orbits. When jumping from one orbit to another with lower energy, a light quantum is emitted..
- In 1916, Niels Bohr became a professor of physics at the University of Copenhagen. In 1920, he was named director of the Institute of Theoretical Physics at the University. In 1922, he was awarded the Nobel Prize in Physics for recognition of his work on the structure of atoms and quantum mechanics. In 1926, Bohr became a Fellow of the Royal.
- Which hypothesis of T's atomic model was later found to be not true by Niels Bohr and why? 2 but later on Bohr predicted that electron just move in a specific energy level and that protons reside in the nucleus. please mark as brainliest. Ramyamgowda456 Ramyamgowda456 Answer: Please mark my answer as brainliest. New questions in.
- hypothesis in the early 1910s. Niels Bohr, in his first attempt to construct a quantum theory in 1916, used it for fundamental purposes in a paper which eventually did not reach the press. He decided not to publish it after having received the new results by Sommerfeld in Munich. Two years later, Bohr published On the quantum theory of line
- Using the Bohr hypothesis, find the frequency of revolution for the electron in the 66'' energy level, in Hz. QUESTION 8 1. Finally, suppose the atomic number of an atom is 25. Find the frequency of a photon emitted if an electron cascades th th from the 6 energy level to the 2 energy level, in Hz. QUESTION 9 1

Bohr was just striving to build an ad hoc theory to account for the hydrogen spectral lines experimented by Balmer. He said it himself: As soon as I saw the Rydberg formula, everything became clear to me. The set hypothesis mvr = nh/2π, matched the predictions and became then the found key formula; that is the angular momentum is quantized.. Among the a priori assumptions by Bohr in his analysis was his famous and unique hypothesis that the only allowed orbits of the electron are such that the angular momentum of the atom is an. **Bohr** conceived a quantum theory for the hydrogen atom Energy and angular momentum are quantized in the **Bohr** theory, which successfully explains Balmer's empirical formula for the spectrum of hydrogen. Historically, the **Bohr** theory is important because it marks the recognition of the atomic domain as the realm of quantum phenomena Development of the Bohr Model. The Bohr model was an improvement on the earlier cubic model (1902), the plum-pudding model (1904), the Saturnian model (1904), and the Rutherford model (1911). Since the Bohr model is a quantum-physics-based modification of the Rutherford model, many sources combine the two: the Rutherford-Bohr model Although revolutionary at the time, the Bohr model is a relatively primitive model of the hydrogen atom compared to the valence shell atom. As an initial hypothesis, it was derived as a first-order approximation to describe the hydrogen atom

- Bohr assumed that the electron orbiting the nucleus would not normally emit any radiation (the stationary state hypothesis), but it would emit or absorb a photon if it moved to a different orbit. The lowest few energy levels are shown in Figure \(\PageIndex{1}\)
- Bohr assumed that the electron orbiting the nucleus would not normally emit any radiation (the stationary state hypothesis), but it would emit or absorb a photon if it moved to a different orbit. The energy absorbed or emitted would reflect differences in the orbital energies according to this equation
- The theory of Bohr is a mixture between the Planck quantum hypothesis and the atomic model of Rutherford
- iature planet, with definite radius and momentum. This is in direct violation of the uncertainty principle which dictates that position and momentum cannot be simultaneously deter
- Rutherford and T. Right at the outset Bohr explicitly called the theories of Rutherford and T atom-model while considering his own theory an attempt at uncovering the constitution of the atom. In so doing, Bohr did not accurately report the works of his two mentors. Since his theory includes Planck's hypothesis and theirs di

- Key Points. Bohr's condition, that the angular momentum is an integer multiple of $\hbar$, was later reinterpreted in 1924 by de Broglie as a standing wave condition.; For what Bohr was forced to hypothesize as the rule for allowed orbits, de Broglie's matter wave concept explains it as the condition for constructive interference of an electron in a circular orbit
- Bohr Model of the Atom Fundamental postulates: The Danish physicist Niels Bohr, who first presented this model of the atom, based it on 3 fundamental postulates. (1) Electrons move around the nucleus in circular non-radiating orbits - called stationary states. However, they are not at rest
- Successes and failures of the Bohr model. Successes: - combining successfully Rutherford's solar system model, with the Planck hypothesis on the quantified energy states at atomic level + Einstein's photons - explaining the atomic emission and absorption spectra - explaining the general features of the periodic tabl
- The Bohr's postulates - 1) An electron can revolve around the nucleus in certain fixed orbits of definite energy without emission of any radiant energy. Such orbits are called stationary orbits. 2) An electron can make a transition from a stationary state of higher energy E_2 to a state of lower energy E_1 and in doing so, it emits a single photon of frequency, nu = (E_2 - E_1)/h where h is.
- Bohr hypothesized that the only way electrons could gain or lose energy would be to move from one energy level to another, thus gaining or losing precise amounts of energy. The energy levels are quantized , meaning that only specific amounts are possible
- Ehrenfest's adiabatic hypothesis in Bohr's quantum theory. It is widely known that Paul Ehrenfest formulated and applied his adiabatic hypothesis in the early 1910s. Niels Bohr, in his first attempt to construct a quantum theory in 1916, used it for fundamental purposes in a paper which eventually did not reach the press

Bohr thought that electrons orbited the nucleus in circular paths; whereas in the modern view atomic electron structure is more like 3D standing waves. Bohr built upon Rutherford's model of the atom. In it most of the atom's mass is concentrated into the center (what we now call the nucleus ) and electrons surround the positive mass in something like a cloud Bohr noticed, however, that the quantum constant formulated by the German physicist Max Planck has dimensions which, when combined with the mass and charge of the electron, produce a measure of length. Numerically, the measure is close to the known size of atoms. This encouraged Bohr to use Planck's constant in searching for a theory of the atom

Bohr Model. Get help with your Bohr model homework. Access the answers to hundreds of Bohr model questions that are explained in a way that's easy for you to understand (a) According to the de-Broglie hypothesis, this electron is also associated with wave character. Hence a circular orbit can be taken to be a stationary energy state only if it contains an integral number of de- Broglie wavelengths i.e. we must have 2πr = nλ According to Bohr's-second postulat According to Bohr's postulate of Quantisation condition, electrons can revolve only in those orbits in which its angular momentum L. So, the circumference of nth stable orbit for an electron can contain exactly n wavelength of de-Broglie(i.e. λ= h/p) associated with the electron in that orbit Bohr's model of the hydrogen atom explains the emission and absorption spectra of atomic hydrogen and hydrogen-like ions with low atomic numbers. It was the first model to introduce the concept of a quantum number to describe atomic states and to postulate quantization of electron orbits in the atom. Bohr's model is an important step in the.

- From de Broglie's hypothesis: λ = h/(mv) So, ultimately we get: mv n r n = nh/(2π) This proved that wave-particle duality is the cause of quantized energy state
- Limitations of Bohr's Atomic Model. The following are the basic limitations of Bohr's Model of the hydrogen atom. It does not comply with the Heisenberg Uncertainty Principle. The Neils Bohr atomic model hypothesis considers electrons to have both known position and momentum simultaneously, which is unthinkable as indicated by Heisenberg
- Solution for A hypothetical atom has atomic number 56. Using the Bohr hypothesis, find the frequency of revolution for the electron in the 63th energy level, i
- Bohr released his atomic theory in 1913. This Bohr's atomic model had some flaws which could not explain some detailed properties in atomic especially in electron motions and orbitals. Louis de Broglie then answered some questions in the Bohr's atomic theory. Here're the correction of Bohr Atomic theory by Louis de Broglie quantum theory
- With A. Sommerfeld's extension of the Bohr theory in 1915-1916, it was turned into a powerful tool of atomic research and adopted and further developed by German physicists in particular. The new and more general Bohr-Sommerfeld theory described the atom in terms of two quantum numbers, while Bohr had originally used only one quantum number
- Bohr Magneton is a unit to express the magnetic moment of an atom due to its orbital or spin angular momentum, generally used in Atomic structure of an atom. The value of Bohr magneton in atomic unit is 1 2. The value of it in SI Unit is 9.274009994 (57)×10^−24 J/T. Hope this helps
- Homework Statement Question: If we assume that an electron is bound to the nucleus (assume a H atom) in a circular orbit, then the Coulomb force is equal to the centripetal force: mv^2/r= ke^2/r^2 In the
**Bohr**hypothesis, angular momentum, L = mvr is quantized as integer multiples of..

Bohr s Quantisation Rule: According to Bohr, an electron can revolve only in certain discrete, non-radiating orbits for which the total angular momentum of the revolving electron is an integral multiple of ; where h is the Planck s constant. That is, b) Using Rydberg s formula for spectra of hydrogen atom, we haveHence, the relation between 3 wavelengths from the energy-level diagram is obtained Bohr's Radius: The radius on which electron move around the nucleus in the orbit described by the Bohr's model is known as Bohr's radius. Using the second postulate and Rutherford's model(eq.1) mvr = nh/(2π) Using the value of υ 2 from both the equations, we get. On solving (and putting Z=1 for hydrogen atom) we get: r = n 2 h 2 Ɛ o. Use De-broglie'S Hypothesis to Write the Relation for the Nth Radius of Bohr Orbit in Terms of Bohr'S Quantization Condition of Orbital Angular Momentum? Concept: de-Broglie Relation. CBSE CBSE (Science) Class 12. Question Papers 1851. Textbook Solutions 13411.. mental evidence for this hypothesis, but de Broglie showed how Bohr's quantisation rules could be de-rived from this hypothesis. Einstein had shown that the light-quantum, or pho-ton, has energy E = h and momentum h=c. De Broglie made the hypothesis that, exactly as in the case of photons, the electron has wave properties such that its.

Niels Bohr. Model of the Atom (Niels Bohr) In 1913 one of Rutherford's students, Niels Bohr, proposed a model for the hydrogen atom that was consistent with Rutherford's model and yet also explained the spectrum of the hydrogen atom. The Bohr model was based on the following assumptions.. 1. The electron in a hydrogen atom travels around the nucleus in a circular orbit It is widely known that Paul Ehrenfest formulated and applied his adiabatic hypothesis in the early 1910s. Niels Bohr, in his first attempt to construct a quantum theory in 1916, used it for. Naturally this was known well before Bohr's model which was simply an extension of the Rutherford model which was an extension of Newtonian orbits. You are probably confusing this with De Broglies hypothesis which was that electrons had waves and that these waves were capable of constructive and destructive interference @inproceedings{JHOSales2005IsTB, title={Is the Bohr's quantization hypothesis necessary ?}, author={J.H.O.Sales and A. Suzuki and D. S. Bonafe}, year={2005} } We deduce the quantization of Bohr's hydrogen's atomic orbit without using his hypothesis of angular momentum quantization. We show that his.

At the point when Bohr was granted the Nobel Prize for his work in 1922, the Hungarian physical scientist Georg Hevesy, together with the physicist Dirk Coster from Holland, were working at Bohr's organization to build up tentatively that the up 'til now unfamiliar nuclear component 72 would carry on as anticipated by Bohr's hypothesis Definition of Bohr Theory. This theory was postulated by a Danish physicist named Neil Bohr in 1922 and has got its name as Bohr atomic model. As this model is the modification of the Rutherford atomic model and so sometimes known as 'Rutherford-Bohr Model'. Bohr model of the atom is rooted in quantum mechanics Obtain Bohr'S Quantisation Condition for Angular Momentum of Electron Orbiting in Nth Orbit in Hydrogen Atom on the Basis of the Wave Picture of an Electron Using De Broglie Hypothesis. Concept: Bohr'S Model for Hydrogen Atom

The Bohr model is simple. It is a 2D model that correctly explains many aspects of the Hydrogen atom, and that is a good starting point for learning about atoms. The Quantum Model represents 3D objects moving in quantum superposition. It gets rid of little dots and replaces them with clouds of probability moving at speeds of a mean speed of 1. Enrico Fermi, the great Italian physicist, was immediately convinced. Building on the discussions held at the Solvay Conference on October 1933 (devoted to James Chadwick's discovery of the neutron), he proposed the theory of beta decay based on a hypothesis that an electron-neutrino pair is spontaneously produced by a nucleus in the same way that photons can spontaneously be emitted by. Abstract. It is widely known that Paul Ehrenfest formulated and applied his adiabatic hypothesis in the early 1910s. Niels Bohr, in his first attempt to construct a quantum theory in 1916, used it for fundamental purposes in a paper which eventually did not reach the press Apr 29, 2018 · The Bohr Diagram. The Bohr Diagram is what scientists use to explain and show an atom's subatomic particles. This technique was created by two scientists in 1913. They are: Niels Bohr and Ernest Rutherford. [14] This drawing is very simple and easy to do. The number of outer shells an atom has is the number of circles drawn ** Niels Bohr and the Quantum Atom is the first book that focuses in detail on the birth and development of Bohr's atomic theory and gives a comprehensive picture of it**. At the same time it offers new insight into Bohr's peculiar way of thinking, what Einstein once called his 'unique instinct and tact'. Contrary to most other accounts of the Bohr atom, the book presents it in a broader.

BOHR MODEL. In 1913, Danish physicist Niels Bohr used the work of Rutherford and Planck to develop his model of the electronic structure of the hydrogen atom. Starting from Rutherford's findings, Bohr assumed that the hydrogen atom consisted of a central proton around which an electron traveled in a circular orbit Niels Bohr Biography: Life & Ideas (1885 - 1962) Niels Henrik David Bohr (October 7, 1885 - November 18, 1962) was a Danish physicist who made essential contributions to understanding atomic structure and quantum mechanics. Niels Bohr's contributions to physics. Bohr's model of atomic structure

The influence of isospin on statistical nuclear decay at approximately 20 MeV is investigated for two composite systems <SUP>66</SUP>Zn and <SUP>64</SUP>Zn by measurement of the cross sections and the energy spectra of protons and α particles emitted from the two composite systems. The composite system <SUP>66</SUP>Zn was formed at an excitation energy of 19.7 MeV in the <SUP>65</SUP>Cu+p and. Bohr's hypothesis: 1) Electrons revolves round the nucleus in water orbits. 2) Orbit of the electron around the nucleus can take only some special values of radius. 3) The energy of the atom as a definite value in these orbits According to the Bohr theory, the probability of finding a hydrogen atoms ground-state electron 0.053 nm from the proton is a. 100%. b. low, but not zero. c. zero. d. high, but not 100%. a. 100%. According to the hypothesis of de Broglie, any moving particle has a. an electric force field. b. a magnetic force field. c. a wavelength. d. energy. Bohr applied the quantum hypothesis to the structure of the atom to explain atomic spectra. Duration: 5:21. Video Quiz. Bohr's Explanation of Atomic Spectra. Bohr proposed that electrons are restricted to particular orbits which he designated by principal quantum numbers. When electrons drop to lower energy levels, they emit light, giving rise. How Bohr's model of hydrogen explains atomic emission spectra. Google Classroom Facebook Twitter. Email. Bohr's model of the hydrogen atom. Light: Electromagnetic waves, the electromagnetic spectrum and photons. Introduction to light. Spectroscopy: Interaction of light and matter. Photoelectric effect

Fits Doesn't fit Bohr's Quantum Hypothesis What's the radius of state n for Hydrogen? What's the radius of state n for Hydrogen? Solving one equation for speed and substituting: What's the radius of state n for Hydrogen? Substituting values for n = 1 yields r = 5.3 x 10-11 m, called the Bohr radius Various postulates of Bohr's atomic model are: 1. In an atom, the electrons revolve around the nucleus in certain definite circular paths called orbits, or shells. 2. Each shell or orbit corresponds to a definite energy. Therefore, these circular orbits are also known as energy levels or energy shells de Broglie's Justification of Bohr's Assumption. de Broglie came up with an explanation for why the angular momentum might be quantized in the manner Bohr assumed it was. de Broglie realized that if you use the wavelength associated with the electron, and assume that an integral number of wavelengths must fit in the circumference of an orbit, you get the same quantized angular momenta that. What were the problems of Bohr's atomic model? The first was that Bohr's atomic model could not explain the many lines present in the spectra of elements with more than one electron. These elements include all the elements after hydrogen on the periodic table. Another was that Bohr thought as if there were actually well-defined orbits in an atom (i) State Bohr's quantization condition for defining stationary orbits. How does de Broglie hypothesis explain the stationary orbits ? (ii) Find the relation between the three wavelength λ 1, λ 2 and λ 3 from the energy level diagram shown below

At the Solvay conference of 1927, however, Bohr successfully refuted all of Einstein's attacks, making use of ingenious gedankenexperiments bearing on a single quantum particle. But in 1935, Einstein raised a new objection about the Copenhagen interpretation, this time with a gedankenexperiment involving two particles. He had discovered that the quantum formalism allows two particles to be entangled in a state such that strong correlations are predicted between measurements on these two. A hipotézis hibásnak bizonyult, mert a körpályán keringő elektron gyorsulása révén energiát kellene kibocsátania, emiatt a magba kellene zuhanjon. Az atom ellenben stabil tulajdonságot mutat. Tananyag ehhez a fogalomhoz: Bohr megállapította, hogy a különböző stacionárius pályák közötti átmenetek feleltethetők meg a. A model proposed by Niels Bohr to support his hypothesis about electrons in a hydrogen atom. This is a model of the atomic structure in which electrons travel around the nucleus in well-defined orbits determined by quantum conditions. A transition from a higher orbit to a lower orbit will release quantized energies of light, which would explain. The Bohr Atom: Consider the electric force between two charges, q1 and q2. The force law is an inverse square law like the gravitational force. The differences is that the constant − G m 1 m 2 is replaced by kq 1 q 2 where k = 8 . 99 H 10 − 11 N − m 2 / C 2 . The minus sign appears because charge is both positive and negative Bohr's second hypothesis in his model was that an electron only loses or releases energy (and therefore a photon) when it goes through de-excitation or drops from a higher energy state to a lower energy state. In order to determine the energy lost by the electron, an expression for an electron's total energy has to be developed

Bohr's quantization principle states that electrons revolve in a stationary orbit of which energy and momentum are fixed. Momentum of an electron in the fixed orbit is given by nh/2, where n is the principal quantum number Bohr-Sommerfeld Quantization Rule Black-body Radiation Problem Called Quantum Numbers Multiperiodic Systems Negligible Deflection These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves The atomic model introduced by Bohr in 1913 dominated the development of the old quantum theory. Its main features, such as the radiationless stationary states and the discontinuous quantum jumps between the states, were hard to swallow for contemporary physicists. While acknowledging the empirical power of the theory, many scientists criticized its foundation or looked for ways to reconcile. In history books, Bohr's chief contribution to physics is usually said to be the Bohr atom — his application in 1912-3 of the still-recent quantum hypothesis to overcome instabilities in Rutherford's solar-system model of the atom, in which electrons travelled in fixed orbits around a positively charged nucleus

It is widely known that Paul Ehrenfest formulated and applied his adiabatic hypothesis in the early 1910s. Niels Bohr, in his first attempt to construct a quantum theory in 1916, used it for fundamental purposes in a paper which eventually did not reach the press. He decided not to publish it after having received the new results by Sommerfeld in Munich Einstein, Bohr and the origins of entanglement. Einstein was the first to publicly support de Broglie's bold hypothesis. By 1926, Erwin Schrödinger had developed a mathematical formula to. The Bohr model of the atom was a planetary model. What did Bohr hypothesize about the atom? Bohr Hypothesized That the atom is a nucleus with electrons orbiting around it Learn quantum mechanics bohr with free interactive flashcards. Choose from 500 different sets of quantum mechanics bohr flashcards on Quizlet Bohr Model of the Atom On the Constitution of Atoms and Molecules Niels Bohr* Philosophical Magazine Series 6, Volume 26 July 1913, p. 1-25 1 In order to explain the results of experiments on scattering of α rays by matter Prof. Rutherford** has given a theory of the structur Broglie hypothesis bohr model >>> next Mind are open only when hearts are open essay wikipedia Best mba essay review service quality south korea faltered agrees with what all looking for the same thing-an all the writings custom henry has studied. Private lives: personal essays on the news of the world and the news of our lives buoyed by an.