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Nutrition👍;
Nutrition is the science that interprets the nutrients and other substances in food in relation to maintenance, growth, reproduction, health and disease of an organism. It includes food intake, absorption, assimilation, biosynthesis, catabolism and excretion.

The diet of an organism is what it eats, which is largely determined by the availability and palatability of foods. For humans, a healthy diet includes preparation of food and storage methods that preserve nutrients from oxidation, heat or leaching, and that reduces risk of foodborne illnesses. The seven major classes of human nutrients are carbohydrates, fats, fiber, minerals, proteins, vitamins, and water. Nutrients can be grouped as either macronutrients or micronutrients (needed in small quantities).

In humans, an unhealthy diet can cause deficiency-related diseases such as blindness, anemia, scurvy, preterm birth, stillbirth and cretinism,or nutrient excess health-threatening conditions such as obesity and metabolic syndrome;and such common chronic systemic diseases as cardiovascular disease, diabetes,and osteoporosis. Undernutrition can lead to wasting in acute cases, and the stunting of marasmus in chronic cases of malnutrition.

Sub:Science(Question with Answer)

PABSON le Class 10(SEE) ko exam yes barsa lina muskil raheko ma exam nade karna students lai certificate dina prastab gareko xa.

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Some question of circle that is need to do construction before solving
Class:10

Qn:22

Sub:C.maths

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Thermodynamics👍👍

Contents👎
1 Introduction👌
2 History✊
3 Etymology✌
4 Branches of thermodynamics👊
4.1 Classical thermodynamics🙂
4.2 Statistical mechanics🙂
4.3 Chemical thermodynamics🙂
4.4 Equilibrium thermodynamic🙂
5 Laws of thermodynamics👉
5.1 Zeroth Law🙂
5.2 First Law🙂
5.3 Second Law🙂
5.4 Third Law🙂

1.Introduction👌
A description of any thermodynamic system employs the four laws of thermodynamics that form an axiomatic basis. The first law specifies that energy can be exchanged between physical systems as heat and work.The second law defines the existence of a quantity called entropy, that describes the direction, thermodynamically, that a system can evolve and quantifies the state of order of a system and that can be used to quantify the useful work that can be extracted from the system.

In thermodynamics, interactions between large ensembles of objects are studied and categorized. Central to this are the concepts of the thermodynamic system and its surroundings. A system is composed of particles, whose average motions define its properties, and those properties are in turn related to one another through equations of state. Properties can be combined to express internal energy and thermodynamic potentials, which are useful for determining conditions for equilibrium and spontaneous processes.

With these tools, thermodynamics can be used to describe how systems respond to changes in their environment. This can be applied to a wide variety of topics in science and engineering, such as engines, phase transitions, chemical reactions, transport phenomena, and even black holes. The results of thermodynamics are essential for other fields of physics and for chemistry, chemical engineering, corrosion engineering, aerospace engineering, mechanical engineering, cell biology, biomedical engineering, materials science, and economics, to name a few.

This article is focused mainly on classical thermodynamics which primarily studies systems in thermodynamic equilibrium. Non-equilibrium thermodynamics is often treated as an extension of the classical treatment, but statistical mechanics has brought many advances to that field.

The thermodynamicists representative of the original eight founding schools of thermodynamics. The schools with the most-lasting effect in founding the modern versions of thermodynamics are the Berlin school, particularly as established in Rudolf Clausius’s 1865 textbook The Mechanical Theory of Heat, the Vienna school, with the statistical mechanics of Ludwig Boltzmann, and the Gibbsian school at Yale University, American engineer Willard Gibbs' 1876 On the Equilibrium of Heterogeneous Substances launching chemical thermodynamics.

2.History✊
The history of thermodynamics as a scientific discipline generally begins with Otto von Guericke who, in 1650, built and designed the world's first vacuum pump and demonstrated a vacuum using his Magdeburg hemispheres. Guericke was driven to make a vacuum in order to disprove Aristotle's long-held supposition that 'nature abhors a vacuum'. Shortly after Guericke, the English physicist and chemist Robert Boyle had learned of Guericke's designs and, in 1656, in coordination with English scientist Robert Hooke, built an air pump.Using this pump, Boyle and Hooke noticed a correlation between pressure, temperature, and volume. In time, Boyle's Law was formulated, which states that pressure and volume are inversely proportional. Then, in 1679, based on these concepts, an associate of Boyle's named Denis Papin built a steam digester, which was a closed vessel with a tightly fitting lid that confined steam until a high pressure was generated.

Later designs implemented a steam release valve that kept the machine from exploding. By watching the valve rhythmically move up and down, Papin conceived of the idea of a piston and a cylinder engine. He did not, however, follow through with his design. Nevertheless, in 1697, based on Papin's designs, engineer Thomas Savery built the first engine, followed by Thomas Newcomen in 1712. Although these early engines were crude and inefficient, they attracted the attention of the leading scientists of the time.

The fundamental concepts of heat capacity and latent heat, which were necessary for the development of thermodynamics, were developed by Professor Joseph Black at the University of Glasgow, where James Watt was employed as an instrument maker. Black and Watt performed experiments together, but it was Watt who conceived the idea of the external condenser which resulted in a large increase in steam engine efficiency. Drawing on all the previous work led Sadi Carnot, the "father of thermodynamics", to publish Reflections on the Motive Power of Fire (1824), a discourse on heat, power, energy and engine efficiency. The book outlined the basic energetic relations between the Carnot engine, the Carnot cycle, and motive power. It marked the start of thermodynamics as a modern science.

The first thermodynamic textbook was written in 1859 by William Rankine, originally trained as a physicist and a civil and mechanical engineering professor at the University of Glasgow.[19] The first and second laws of thermodynamics emerged simultaneously in the 1850s, primarily out of the works of William Rankine, Rudolf Clausius, and William Thomson (Lord Kelvin).
The foundations of statistical thermodynamics were set out by physicists such as James Clerk Maxwell, Ludwig Boltzmann, Max Planck, Rudolf Clausius and J. Willard Gibbs.

During the years 1873–76 the American mathematical physicist Josiah Willard Gibbs published a series of three papers, the most famous being On the Equilibrium of Heterogeneous Substances,in which he showed how thermodynamic processes, including chemical reactions, could be graphically analyzed, by studying the energy, entropy, volume, temperature and pressure of the thermodynamic system in such a manner, one can determine if a process would occur spontaneously. Also Pierre Duhem in the 19th century wrote about chemical thermodynamics. During the early 20th century, chemists such as Gilbert N. Lewis, Merle Randall,and E. A. Guggenheim applied the mathematical methods of Gibbs to the analysis of chemical processes.

3.Etymology✌
The etymology of thermodynamics has an intricate history.It was first spelled in a hyphenated form as an adjective (thermo-dynamic) and from 1854 to 1868 as the noun thermo-dynamics to represent the science of generalized heat engines.

American biophysicist Donald Haynie claims that thermodynamics was coined in 1840 from the Greek root θέρμη therme, meaning “heat”, and δύναμις dynamis, meaning “power”.

Pierre Perrot claims that the term thermodynamics was coined by James Joule in 1858 to designate the science of relations between heat and power, however, Joule never used that term, but used instead the term perfect thermo-dynamic engine in reference to Thomson's 1849 phraseology.

By 1858, thermo-dynamics, as a functional term, was used in William Thomson's paper "An Account of Carnot's Theory of the Motive Power of Heat."

4.Branches of thermodynamics👊
The study of thermodynamical systems has developed into several related branches, each using a different fundamental model as a theoretical or experimental basis, or applying the principles to varying types of systems.

4.1.Classical thermodynamics🙂
Classical thermodynamics is the description of the states of thermodynamic systems at near-equilibrium, that uses macroscopic, measurable properties. It is used to model exchanges of energy, work and heat based on the laws of thermodynamics. The qualifier classical reflects the fact that it represents the first level of understanding of the subject as it developed in the 19th century and describes the changes of a system in terms of macroscopic empirical (large scale, and measurable) parameters. A microscopic interpretation of these concepts was later provided by the development of statistical mechanics.

4.2.Statistical mechanics🙂
Statistical mechanics, also called statistical thermodynamics, emerged with the development of atomic and molecular theories in the late 19th century and early 20th century, and supplemented classical thermodynamics with an interpretation of the microscopic interactions between individual particles or quantum-mechanical states. This field relates the microscopic properties of individual atoms and molecules to the macroscopic, bulk properties of materials that can be observed on the human scale, thereby explaining classical thermodynamics as a natural result of statistics, classical mechanics, and quantum theory at the microscopic level.

4.3.Chemical thermodynamics🙂
Chemical thermodynamics is the study of the interrelation of energy with chemical reactions or with a physical change of state within the confines of the laws of thermodynamics.

4.4.Equilibrium thermodynamics🙂
Equilibrium thermodynamics is the study of transfers of matter and energy in systems or bodies that, by agencies in their surroundings, can be driven from one state of thermodynamic equilibrium to another. The term 'thermodynamic equilibrium' indicates a state of balance, in which all macroscopic flows are zero; in the case of the simplest systems or bodies, their intensive properties are homogeneous, and their pressures are perpendicular to their boundaries. In an equilibrium state there are no unbalanced potentials, or driving forces, between macroscopically distinct parts of the system. A central aim in equilibrium thermodynamics is: given a system in a well-defined initial equilibrium state, and given its surroundings, and given its constitutive walls, to calculate what will be the final equilibrium state of the system after a specified thermodynamic operation has changed its walls or surroundings.

Non-equilibrium thermodynamics is a branch of thermodynamics that deals with systems that are not in thermodynamic equilibrium. Most systems found in nature are not in thermodynamic equilibrium because they are not in stationary states, and are continuously and discontinuously subject to flux of matter and energy to and from other systems. The thermodynamic study of non-equilibrium systems requires more general concepts than are dealt with by equilibrium thermodynamics. Many natural systems still today remain beyond the scope of currently known macroscopic thermodynamic methods.

5.Laws of thermodynamics👉
Main article: Laws of thermodynamics
Thermodynamics is principally based on a set of four laws which are universally valid when applied to systems that fall within the constraints implied by each. In the various theoretical descriptions of thermodynamics these laws may be expressed in seemingly differing forms, but the most prominent formulations are the following.

5.1.Zeroth Law🙂
The zeroth law of thermodynamics states: If two systems are each in thermal equilibrium with a third, they are also in thermal equilibrium with each other.

This statement implies that thermal equilibrium is an equivalence relation on the set of thermodynamic systems under consideration. Systems are said to be in equilibrium if the small, random exchanges between them (e.g. Brownian motion) do not lead to a net change in energy. This law is tacitly assumed in every measurement of temperature. Thus, if one seeks to decide whether two bodies are at the same temperature, it is not necessary to bring them into contact and measure any changes of their observable properties in time. The law provides an empirical definition of temperature, and justification for the construction of practical thermometers.

The zeroth law was not initially recognized as a separate law of thermodynamics, as its basis in thermodynamical equilibrium was implied in the other laws. The first, second, and third laws had been explicitly stated already, and found common acceptance in the physics community before the importance of the zeroth law for the definition of temperature was realized. As it was impractical to renumber the other laws, it was named the zeroth law.

5.2.First Law🙂
The first law of thermodynamics states: In a process without transfer of matter, the change in internal energy, ΔU, of a thermodynamic system is equal to the energy gained as heat, Q, less the thermodynamic work, W, done by the system on its surroundings.
ΔU=Q-W
For processes that include transfer of matter, a further statement is needed: With due account of the respective fiducial reference states of the systems, when two systems, which may be of different chemical compositions, initially separated only by an impermeable wall, and otherwise isolated, are combined into a new system by the thermodynamic operation of removal of the wall, then
Uo=U1+U2
where U0 denotes the internal energy of the combined system, and U1 and U2 denote the internal energies of the respective separated systems.

Adapted for thermodynamics, this law is an expression of the principle of conservation of energy, which states that energy can be transformed (changed from one form to another), but cannot be created or destroyed.[

Internal energy is a principal property of the thermodynamic state, while heat and work are modes of energy transfer by which a process may change this state. A change of internal energy of a system may be achieved by any combination of heat added or removed and work performed on or by the system. As a function of state, the internal energy does not depend on the manner, or on the path through intermediate steps, by which the system arrived at its state.

5.3.Second Law🙂
The second law of thermodynamics states: Heat cannot spontaneously flow from a colder location to a hotter location.

This law is an expression of the universal principle of decay observable in nature. The second law is an observation of the fact that over time, differences in temperature, pressure, and chemical potential tend to even out in a physical system that is isolated from the outside world. Entropy is a measure of how much this process has progressed. The entropy of an isolated system which is not in equilibrium will tend to increase over time, approaching a maximum value at equilibrium. However, principles guiding systems that are far from equilibrium are still debatable. One of such principles is the maximum entropy production principle.It states that non-equilibrium systems behave such a way as to maximize its entropy production.

In classical thermodynamics, the second law is a basic postulate applicable to any system involving heat energy transfer; in statistical thermodynamics, the second law is a consequence of the assumed randomness of molecular chaos. There are many versions of the second law, but they all have the same effect, which is to explain the phenomenon of irreversibility in nature.

5.4.Third Law🙂
The third law of thermodynamics states: As the temperature of a system approaches absolute zero, all processes cease and the entropy of the system approaches a minimum value.

This law of thermodynamics is a statistical law of nature regarding entropy and the impossibility of reaching absolute zero of temperature. This law provides an absolute reference point for the determination of entropy. The entropy determined relative to this point is the absolute entropy. Alternate definitions include "the entropy of all systems and of all states of a system is smallest at absolute zero," or equivalently "it is impossible to reach the absolute zero of temperature by any finite number of processes".

Absolute zero, at which all activity would stop if it were possible to achieve, is −273.15 °C (degrees Celsius), or −459.67 °F (degrees Fahrenheit), or 0 K (kelvin), or 0° R (degrees Rankine).

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Sub: Science
Grade:10 and 9
History Of Earth

Some of the hypothesis related to origin of earth:
1. Planetesimal Hypothesis(George Wofan Hypothesis)
2. Nebular Hypothesis(Kant's Hypothesis)
3. Tidal Hypothesis(Jeans and Jeffreys Hypothesis)

Explanation

🙂.Planetesimal Hypothesis(George Wofan Hypothesis):
This hypothesis was pro-founded by George Wofan. According to this hypothesis, the earth and solar system was formed when comet revolving around the universe struck to the sun. The comets break down into pieces and change into planet, satellites.
Thus, solar system is formed.
Objection:How is sun formed.?

🙂.Nebular Hypothesis(Kant,s Hypothesis):
This hypothesis was pro-founded by Immanuel kant. According to this hypothesis, the solar system is formed from nebula. Nebula is large cloud of charged dust particles. Slowly and gradually its size started to decrease as a result its rotation speed increases. With increase of its rotation, a gaseous rings separated from nebula. Later, the rings cooled and took the form of planet. And center mass is formed as sun.
Thus, solar system is formed.
Objection: How the hot gaseous materials condensed into rings?

🙂.Tidal Hypothesis(Jeans and Jeffreys Hypothesis):
This hypothesis was pro-founded by Sir James Jeans and Sir Harold Jeffreys. According to this hypothesis, planet and satellite are formed from gaseous tide. A large star come near to the sun, due to gravitational pills of sun, a gaseous tide was separated from star. The gaseous tide detached when star moved away. The shape of tide is like a spindle.The tide break broken into pieces and forms planets and satellite.
Thus, solar system is formed.
Objection: How the tide condensed into spindle shaped?

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Sub:Account
Grade;10
Report
Introduction:👉
A report is a written statement of jobs done by an organization, committee, commission, etc. for a particular period of time. It includes the details about problems, progress, achievements, facts, information etc. regarding the problems under study. So, it is called historical statement.

Types of report
1.Annual report
2.Government report
3.Audit report
4.Academic report
5.Committee report

Explanation:✌️

🙂.Annual Report:
The report covering the activities, progress and achievements made in a particular year is called Annual Report. It is prepared by all kinds of organizations to measure their performance over the year. In companies, annual report comprising of financial documents is presented at general meeting for approval by shareholders.

🙂.Government Report
A government is always accountable to general public. So a report is prepared by government to make people aware about its activities, plans, policies, revenues or incomes, expenditures etc. which is called a government report. Based on this report, people can judge on the efficiency of the government.

🙂.Audit Report
A report regarding the preparation and communication of financial information of an organization prepared by the auditor is called audit report. It checks whether financial transactions are carried out within existing rules and regulations. Auditor General and independent auditor prepares the audit report for government organization and public company respectively.

🙂.Academic Report
A report prepared by students or academic institution after completion of the examination or study or research is called academic report. The content of the report is related to educational or academic activities.

🙂.Committee Report
A committee is group of experts formed to achieve a particular objective by carrying out certain activities. The very report prepared by members of committee after completion of designated job is called committee report. It is submitted to concerned authority for approval and implementation.

Consideration of preparing report:✌️

🙂.The title of report along with date and subject should be established on top of the report.
🙂.The time frame covered by the report should be clear.
🙂.The information should be represented in such manner that they are comprehensive and communicative.
🙂.Report must incorporate the opinions and suggestions of the report writer.
🙂.Finally, report must be duly signed by the prepare to retain its validity.