The document discusses thermal expansion in solids. It explains that solids expand when heated as the internal energy of atoms increases, causing them to vibrate and occupy more space. This is why gaps are left between railway tracks - to allow for expansion on hot days which could otherwise cause bending and accidents. Equations of linear, area, and volume expansion are provided, stating the change is proportional to the initial measurement and temperature change.
process, Thermodynamic process,workdone, relation between pressure volume,first law of thermodynamic,need of second law,statement of second law,carnot heat engine,efficiency,numericals
This document discusses thermodynamic properties and relations. Some key points:
- Thermodynamic properties that cannot be directly measured must be related to measurable properties.
- Properties are continuous point functions that have exact differentials and can be written as functions of two independent variables like z(x,y).
- The Maxwell relations relate the partial derivatives of properties like pressure, specific volume, temperature and entropy.
- The Clapeyron equation relates the enthalpy change of phase change to the slope of the saturation curve on a pressure-temperature diagram.
- Specific heats, internal energy, enthalpy and entropy changes can be expressed in terms of pressure, specific volume, temperature and specific he
This document discusses various topics related to heat transfer including the three main modes of heat transfer: conduction, convection, and radiation. It provides the governing equations for each, including Fourier's law of conduction, Newton's law of cooling for convection, and Stefan-Boltzmann law for radiation. Specific topics covered include steady state and transient conduction, extended surfaces, heat exchangers, and free and forced convection. Equations are also derived for one-dimensional conduction under steady state conditions with and without heat generation.
Temperature measurement is important across many industries and applications. There are several common temperature sensors including glass thermometers, bi-metallic thermometers, RTDs, thermocouples, thermistors, and IC sensors. Each sensor has advantages and disadvantages depending on factors like required accuracy, temperature range, cost, and environment. Proper sensor selection requires considering the application and prioritizing parameters like standards, stability, sensitivity, size, and contact vs non-contact measurement.
Heat conduction is the transfer of heat from one body to another through direct contact. It mainly occurs in solids via molecular interactions and lattice vibrations, and in metals also via the drift of free electrons. Heat conduction follows Fourier's law, where the rate of heat transfer is proportional to the temperature gradient and thermal conductivity of the material. Thermal conductivity varies with temperature and is highest in metals like silver and copper. The lumped heat analysis method can be used to simplify problems involving transient heat conduction when the Biot number is low (<0.1), by assuming the temperature inside a solid is uniform.
The document discusses thermal expansion in solids. It explains that solids expand when heated as the internal energy of atoms increases, causing them to vibrate and occupy more space. This is why gaps are left between railway tracks - to allow for expansion on hot days which could otherwise cause bending and accidents. Equations of linear, area, and volume expansion are provided, stating the change is proportional to the initial measurement and temperature change.
process, Thermodynamic process,workdone, relation between pressure volume,first law of thermodynamic,need of second law,statement of second law,carnot heat engine,efficiency,numericals
This document discusses thermodynamic properties and relations. Some key points:
- Thermodynamic properties that cannot be directly measured must be related to measurable properties.
- Properties are continuous point functions that have exact differentials and can be written as functions of two independent variables like z(x,y).
- The Maxwell relations relate the partial derivatives of properties like pressure, specific volume, temperature and entropy.
- The Clapeyron equation relates the enthalpy change of phase change to the slope of the saturation curve on a pressure-temperature diagram.
- Specific heats, internal energy, enthalpy and entropy changes can be expressed in terms of pressure, specific volume, temperature and specific he
This document discusses various topics related to heat transfer including the three main modes of heat transfer: conduction, convection, and radiation. It provides the governing equations for each, including Fourier's law of conduction, Newton's law of cooling for convection, and Stefan-Boltzmann law for radiation. Specific topics covered include steady state and transient conduction, extended surfaces, heat exchangers, and free and forced convection. Equations are also derived for one-dimensional conduction under steady state conditions with and without heat generation.
Temperature measurement is important across many industries and applications. There are several common temperature sensors including glass thermometers, bi-metallic thermometers, RTDs, thermocouples, thermistors, and IC sensors. Each sensor has advantages and disadvantages depending on factors like required accuracy, temperature range, cost, and environment. Proper sensor selection requires considering the application and prioritizing parameters like standards, stability, sensitivity, size, and contact vs non-contact measurement.
Heat conduction is the transfer of heat from one body to another through direct contact. It mainly occurs in solids via molecular interactions and lattice vibrations, and in metals also via the drift of free electrons. Heat conduction follows Fourier's law, where the rate of heat transfer is proportional to the temperature gradient and thermal conductivity of the material. Thermal conductivity varies with temperature and is highest in metals like silver and copper. The lumped heat analysis method can be used to simplify problems involving transient heat conduction when the Biot number is low (<0.1), by assuming the temperature inside a solid is uniform.
The document discusses the triple point of substances, which is the specific temperature and pressure at which the solid, liquid, and gas phases of a single substance can coexist in equilibrium. It provides the triple point values for water, which is 0.01°C and 611.73 pascals, as well as table listing the triple point temperatures and pressures of various substances including helium, hydrogen, oxygen, nitrogen, ammonia, and carbon dioxide.
Sorces of errors in a filled system thermometerTejas Atyam
another ppt for a class presentation . I admit it is a bit incomplete but this is all I got as a topic for explanation . I hope you guys gain from it !
This lab manual document provides instructions for experiments on heat transfer in a Mechanical Engineering department. The first experiment listed is on heat transfer from a pin-fin apparatus. The objective is to calculate the heat transfer coefficient for natural and forced convection from a fin. The experiment involves measuring temperatures along a brass fin heated at one end while air passes over it naturally or in a duct. The second experiment listed is on heat transfer through a composite wall, and involves determining the total thermal resistance and conductivity of a wall made of different slab materials sandwiching a heater.
Thermodynamic Chapter 4 Second Law Of ThermodynamicsMuhammad Surahman
This document provides an overview of the second law of thermodynamics. It discusses how the second law establishes conditions for equilibrium and determines theoretical performance limits. The document defines key concepts like thermal efficiency, the Carnot cycle, and entropy. It presents examples calculating efficiency and heat transfer for systems like power plants, refrigerators, and heat pumps operating between different temperature levels.
This document discusses Fourier's law of heat conduction and the heat equation. It begins by recapping one-dimensional steady-state conduction and then discusses applying Fourier's law to different geometries. It derives the general heat conduction equation and describes how to write it for Cartesian, cylindrical, and spherical coordinate systems. Special cases of the heat equation like steady-state, no heat generation, and transient conditions are also covered. The document concludes by discussing the necessary boundary and initial conditions required to solve the heat equation.
When objects are heated, they expand due to thermal expansion. Thermal expansion occurs because the energy stored in the intermolecular bonds between atoms increases with temperature, causing the molecular bonds to lengthen. Examples of applications of thermal expansion include metal framed windows using rubber spacers, metal hot water pipes avoiding long straight lengths, and large structures like bridges employing expansion joints. Thermometers also demonstrate thermal expansion through the constrained flow of liquid in a tube due to changes in volume from temperature variations.
Heat capacity is the amount of heat needed to raise a system's temperature by one degree, expressed in units of thermal energy per degree. Specific heat capacity is the amount of heat needed to increase the temperature of one kilogram of a substance by one degree, expressed in joules per kg per degree Kelvin. The document provides formulas for heat capacity and specific heat capacity, and gives an example quiz to test understanding of specific heat capacity definitions and calculations involving changes in temperature and heat energy.
This document provides an overview of different temperature measurement devices and concepts. It discusses liquid-in-glass thermometers, bimetallic thermometers, pressure/filled system thermometers including classifications based on liquid, vapor, gas and mercury filling. It also covers electrical temperature measurement using resistance temperature detectors (RTDs), thermistors, and thermocouples. Sources of error and advantages/disadvantages are described for each type of temperature measuring device.
Mechanical temperature measuring devices and their applicationsAnand Prithviraj
The document discusses various mechanical temperature measurement devices. It describes five main types: liquid-in-glass thermometers, pressure thermometers, bimetallic thermometers, sealed bellows, and bulb and capillary sensors. Each type uses the mechanical effects of thermal expansion to infer temperature changes by measuring volume, pressure, or motion. While some devices like thermometers are centuries old, mechanical sensors remain widely used for their reliability, cost-effectiveness, and ability to function without external power sources.
The Carnot Cycle describes an ideal thermodynamic cycle consisting of four reversible processes involving any substance: (1) reversible isothermal expansion, (2) reversible adiabatic expansion, (3) reversible isothermal compression, and (4) reversible adiabatic compression. The efficiency of the Carnot Cycle, known as the Carnot efficiency, is the maximum possible efficiency for any heat engine operating between two temperature reservoirs and is equal to 1 - (TL/TH), where TL and TH are the temperatures of the low and high reservoirs.
The document discusses the phase behavior of pure substances through P-T and P-V diagrams. A P-T diagram shows the relationships between pressure, temperature, and phases (solid, liquid, gas). Key points on the diagram include the sublimation, fusion, and vaporization curves that separate the phases and meet at the triple point. The critical point marks the highest P and T where the substance can exist as a liquid and gas. A P-V diagram adds volume information and shows isotherms representing constant temperature lines that intersect phase boundaries.
This document discusses the McCabe-Thiele method for designing binary distillation columns. The method uses vapor-liquid equilibrium (VLE) data to graphically determine the theoretical number of stages required for separation. Operating lines are drawn on the VLE diagram based on the desired compositions of top and bottom products. Where these lines intersect represents equilibrium stages. The number of intersections equals the number of theoretical stages. Additional trays are needed based on tray efficiency. The feed point can also be determined from its vapor-liquid condition. Overall column design requires considering additional factors like tray spacing, diameter, and heating/cooling duties through an iterative process.
This document discusses heat exchangers, specifically double pipe and shell and tube heat exchangers. It defines heat exchangers as devices used to transfer heat between fluids or between fluids and solids. It then describes the basic construction and working principles of double pipe heat exchangers, including their applications in areas like aircraft and commercial uses. The document also briefly introduces shell and tube heat exchangers.
1) A nanosecond laser photolysis technique was used to measure the rate constants of Ru(bpy)3
2+ phosphorescence quenching, spontaneous fluorescence decay, and nonradiative relaxation.
2) The rate constant for quenching by oxygen (kq) was measured to be 3.008x1011±2.740x1010 M-1 s-1. The rate constant for fluorescence and nonradiative relaxation (kf+knr) was measured to be 3.67x106±8.98x105 s-1.
3) Samples saturated with air, oxygen, and nitrogen were exposed to laser pulses and their intensities over time were measured. Exponential fits to the
NEED FOR THE SECOND LAW OF THERMODYNAMICS - STATEMENT - CARNOT CYCLE - REFRIGERATOR CONCEPT - CONCEPT OF ENTROPY - FREE ENERGY FUNCTIONS - GIBB'S HELMHOLTZ EQUATIONS - MAXEWELL'S RELATIONS - THERMODYNAMICS EQUATION OF STATE - CRITERIA OF SPONTANITY - CHEMICAL POTENTIAL - GIBB'S DUHEM EQUATION
Lecture 4 (b) Reversible and Irreversible processes.pptxHassan Yousaf
1) A reversible process is one that can proceed in either direction, returning both the system and surroundings to their original states. It occurs through infinitesimally small steps and involves no friction.
2) An irreversible process cannot reverse direction and results in a permanent change to the system or surroundings. Examples include tearing paper or free expansion of a gas into a vacuum.
3) Reversible processes are idealizations since real processes involve some irreversibility. However, the concept is important because it establishes the minimum heat and maximum work values for a given change between states.
This contains a basic idea about viscosity measurement devices and their principles. Working, principle, construction, and advantages of rotating viscometer are described here.
This document provides an overview of basic chemistry concepts including:
- The law of multiple proportions and how it is illustrated by nitrogen and hydrogen oxides.
- Definitions of a mole and how it is used to calculate the number of hydrogen atoms in 1 mole of methane.
- How stoichiometry is used to calculate the amount of water formed from the combustion of a given amount of methane.
- The concept of a limiting reagent and how to calculate the mass of a product given specific amounts of reactants.
- A summary of the key observations and conclusions from Rutherford's gold foil experiment that led to the nuclear model of the atom.
- The document discusses quantum theory of radiation and blackbody radiation. It introduces Planck's hypothesis that oscillators can only absorb and emit energy in discrete quanta proportional to frequency to solve the ultraviolet catastrophe.
- Planck's radiation law gives the spectral density of electromagnetic radiation emitted by a black body in thermal equilibrium. It was derived using the assumptions that oscillators have discrete energy levels and Boltzmann statistics.
- The Rayleigh-Jeans law, derived from classical physics, correctly predicted blackbody radiation at long wavelengths but failed at short wavelengths, known as the ultraviolet catastrophe. Planck's hypothesis resolved this issue.
The document discusses the triple point of substances, which is the specific temperature and pressure at which the solid, liquid, and gas phases of a single substance can coexist in equilibrium. It provides the triple point values for water, which is 0.01°C and 611.73 pascals, as well as table listing the triple point temperatures and pressures of various substances including helium, hydrogen, oxygen, nitrogen, ammonia, and carbon dioxide.
Sorces of errors in a filled system thermometerTejas Atyam
another ppt for a class presentation . I admit it is a bit incomplete but this is all I got as a topic for explanation . I hope you guys gain from it !
This lab manual document provides instructions for experiments on heat transfer in a Mechanical Engineering department. The first experiment listed is on heat transfer from a pin-fin apparatus. The objective is to calculate the heat transfer coefficient for natural and forced convection from a fin. The experiment involves measuring temperatures along a brass fin heated at one end while air passes over it naturally or in a duct. The second experiment listed is on heat transfer through a composite wall, and involves determining the total thermal resistance and conductivity of a wall made of different slab materials sandwiching a heater.
Thermodynamic Chapter 4 Second Law Of ThermodynamicsMuhammad Surahman
This document provides an overview of the second law of thermodynamics. It discusses how the second law establishes conditions for equilibrium and determines theoretical performance limits. The document defines key concepts like thermal efficiency, the Carnot cycle, and entropy. It presents examples calculating efficiency and heat transfer for systems like power plants, refrigerators, and heat pumps operating between different temperature levels.
This document discusses Fourier's law of heat conduction and the heat equation. It begins by recapping one-dimensional steady-state conduction and then discusses applying Fourier's law to different geometries. It derives the general heat conduction equation and describes how to write it for Cartesian, cylindrical, and spherical coordinate systems. Special cases of the heat equation like steady-state, no heat generation, and transient conditions are also covered. The document concludes by discussing the necessary boundary and initial conditions required to solve the heat equation.
When objects are heated, they expand due to thermal expansion. Thermal expansion occurs because the energy stored in the intermolecular bonds between atoms increases with temperature, causing the molecular bonds to lengthen. Examples of applications of thermal expansion include metal framed windows using rubber spacers, metal hot water pipes avoiding long straight lengths, and large structures like bridges employing expansion joints. Thermometers also demonstrate thermal expansion through the constrained flow of liquid in a tube due to changes in volume from temperature variations.
Heat capacity is the amount of heat needed to raise a system's temperature by one degree, expressed in units of thermal energy per degree. Specific heat capacity is the amount of heat needed to increase the temperature of one kilogram of a substance by one degree, expressed in joules per kg per degree Kelvin. The document provides formulas for heat capacity and specific heat capacity, and gives an example quiz to test understanding of specific heat capacity definitions and calculations involving changes in temperature and heat energy.
This document provides an overview of different temperature measurement devices and concepts. It discusses liquid-in-glass thermometers, bimetallic thermometers, pressure/filled system thermometers including classifications based on liquid, vapor, gas and mercury filling. It also covers electrical temperature measurement using resistance temperature detectors (RTDs), thermistors, and thermocouples. Sources of error and advantages/disadvantages are described for each type of temperature measuring device.
Mechanical temperature measuring devices and their applicationsAnand Prithviraj
The document discusses various mechanical temperature measurement devices. It describes five main types: liquid-in-glass thermometers, pressure thermometers, bimetallic thermometers, sealed bellows, and bulb and capillary sensors. Each type uses the mechanical effects of thermal expansion to infer temperature changes by measuring volume, pressure, or motion. While some devices like thermometers are centuries old, mechanical sensors remain widely used for their reliability, cost-effectiveness, and ability to function without external power sources.
The Carnot Cycle describes an ideal thermodynamic cycle consisting of four reversible processes involving any substance: (1) reversible isothermal expansion, (2) reversible adiabatic expansion, (3) reversible isothermal compression, and (4) reversible adiabatic compression. The efficiency of the Carnot Cycle, known as the Carnot efficiency, is the maximum possible efficiency for any heat engine operating between two temperature reservoirs and is equal to 1 - (TL/TH), where TL and TH are the temperatures of the low and high reservoirs.
The document discusses the phase behavior of pure substances through P-T and P-V diagrams. A P-T diagram shows the relationships between pressure, temperature, and phases (solid, liquid, gas). Key points on the diagram include the sublimation, fusion, and vaporization curves that separate the phases and meet at the triple point. The critical point marks the highest P and T where the substance can exist as a liquid and gas. A P-V diagram adds volume information and shows isotherms representing constant temperature lines that intersect phase boundaries.
This document discusses the McCabe-Thiele method for designing binary distillation columns. The method uses vapor-liquid equilibrium (VLE) data to graphically determine the theoretical number of stages required for separation. Operating lines are drawn on the VLE diagram based on the desired compositions of top and bottom products. Where these lines intersect represents equilibrium stages. The number of intersections equals the number of theoretical stages. Additional trays are needed based on tray efficiency. The feed point can also be determined from its vapor-liquid condition. Overall column design requires considering additional factors like tray spacing, diameter, and heating/cooling duties through an iterative process.
This document discusses heat exchangers, specifically double pipe and shell and tube heat exchangers. It defines heat exchangers as devices used to transfer heat between fluids or between fluids and solids. It then describes the basic construction and working principles of double pipe heat exchangers, including their applications in areas like aircraft and commercial uses. The document also briefly introduces shell and tube heat exchangers.
1) A nanosecond laser photolysis technique was used to measure the rate constants of Ru(bpy)3
2+ phosphorescence quenching, spontaneous fluorescence decay, and nonradiative relaxation.
2) The rate constant for quenching by oxygen (kq) was measured to be 3.008x1011±2.740x1010 M-1 s-1. The rate constant for fluorescence and nonradiative relaxation (kf+knr) was measured to be 3.67x106±8.98x105 s-1.
3) Samples saturated with air, oxygen, and nitrogen were exposed to laser pulses and their intensities over time were measured. Exponential fits to the
NEED FOR THE SECOND LAW OF THERMODYNAMICS - STATEMENT - CARNOT CYCLE - REFRIGERATOR CONCEPT - CONCEPT OF ENTROPY - FREE ENERGY FUNCTIONS - GIBB'S HELMHOLTZ EQUATIONS - MAXEWELL'S RELATIONS - THERMODYNAMICS EQUATION OF STATE - CRITERIA OF SPONTANITY - CHEMICAL POTENTIAL - GIBB'S DUHEM EQUATION
Lecture 4 (b) Reversible and Irreversible processes.pptxHassan Yousaf
1) A reversible process is one that can proceed in either direction, returning both the system and surroundings to their original states. It occurs through infinitesimally small steps and involves no friction.
2) An irreversible process cannot reverse direction and results in a permanent change to the system or surroundings. Examples include tearing paper or free expansion of a gas into a vacuum.
3) Reversible processes are idealizations since real processes involve some irreversibility. However, the concept is important because it establishes the minimum heat and maximum work values for a given change between states.
This contains a basic idea about viscosity measurement devices and their principles. Working, principle, construction, and advantages of rotating viscometer are described here.
This document provides an overview of basic chemistry concepts including:
- The law of multiple proportions and how it is illustrated by nitrogen and hydrogen oxides.
- Definitions of a mole and how it is used to calculate the number of hydrogen atoms in 1 mole of methane.
- How stoichiometry is used to calculate the amount of water formed from the combustion of a given amount of methane.
- The concept of a limiting reagent and how to calculate the mass of a product given specific amounts of reactants.
- A summary of the key observations and conclusions from Rutherford's gold foil experiment that led to the nuclear model of the atom.
- The document discusses quantum theory of radiation and blackbody radiation. It introduces Planck's hypothesis that oscillators can only absorb and emit energy in discrete quanta proportional to frequency to solve the ultraviolet catastrophe.
- Planck's radiation law gives the spectral density of electromagnetic radiation emitted by a black body in thermal equilibrium. It was derived using the assumptions that oscillators have discrete energy levels and Boltzmann statistics.
- The Rayleigh-Jeans law, derived from classical physics, correctly predicted blackbody radiation at long wavelengths but failed at short wavelengths, known as the ultraviolet catastrophe. Planck's hypothesis resolved this issue.
This document defines various terms associated with elements and their subatomic particles. It then summarizes Rutherford's gold foil experiment and conclusions that led to the nuclear model of the atom. The document continues by describing the key subatomic particles (protons, neutrons, electrons), electromagnetic spectrum, photoelectric effect, atomic spectra, Bohr's model of the hydrogen atom, de Broglie wavelength, Heisenberg's uncertainty principle, Schrodinger wave equation, shapes of orbitals, filling of orbitals according to Aufbau principle and Hund's rule.
I am Samantha K. I am a Statistical Physics Assignment Expert at statisticsassignmenthelp.com. I hold a Masters in Statistics from, McGill University, Canada
I have been helping students with their homework for the past 8 years. I solve assignments related to Statistics.
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You can also call on +1 678 648 4277 for any assistance with Statistical Physics Assignments.
The document provides contact information for Statistics Homework Helper, including their website, email address, and phone number. It offers help with Statistics Homework through online tutoring services.
1) Classical mechanics and Maxwell's equations can explain macroscopic phenomena but quantum mechanics is needed to explain microscopic phenomena such as atomic structure.
2) Quantum mechanics arose from the need to explain physical phenomena not accounted for by classical physics, including blackbody radiation, the photoelectric effect, atomic spectra, and specific heat of solids.
3) Experiments such as the photoelectric effect, Compton effect, diffraction of electrons demonstrated that particles have wave-like properties and waves have particle-like properties, showing the need for a new theoretical framework that incorporated wave-particle duality.
This document outlines the program for a Physics 2 course covering fluid mechanics and thermal physics. It includes 5 chapters: fluid mechanics, heat and temperature, heat and the first law of thermodynamics, the kinetic theory of gases, and entropy and the second law of thermodynamics. References and websites for further information are also provided. The document then provides an in-depth overview of Chapter 4 on the kinetic theory of gases, covering topics like the molecular model of an ideal gas, the equipartition of energy, and the Boltzmann distribution law. It includes examples and problems related to these concepts.
Med.physics dr. ismail atomic and nuclear physics Ismail Syed
This document discusses various topics in nuclear and atomic physics including:
- Photon and electromagnetic radiation being quantized into particles called photons according to Einstein's theory.
- Photoelectric effect where photons eject electrons from metal surfaces.
- De Broglie hypothesis of matter waves associated with moving particles.
- Rutherford's model of the atom consisting of a small, dense nucleus surrounded by electrons.
- Isotopes being nuclei with the same number of protons but different numbers of neutrons.
- Nuclear radius increasing with the cube root of the atomic mass number based on measurements.
- Radioactive decay, half life, activity, and the relationship between decay constant and half life.
This document contains a physics exam with multiple choice and free response questions covering topics like the photoelectric effect, quantization of energy, nuclear physics, wave-particle duality, and more. The exam has sections on multiple choice questions with 16 total questions, explanations of concepts to short responses, and 9 physics problems to solve.
PHYSICS CLASS XII Chapter 3 - Kinetic theory of gases and radiationPooja M
The document discusses the kinetic theory of gases and heat radiation. It explains that gases are made up of molecules in random motion, and describes their behavior using concepts like pressure, temperature, mean free path and degrees of freedom. Ideal gases have no intermolecular forces, while real gases do. The document also discusses heat radiation, defining concepts like blackbody radiation, emissivity, and formulating laws like Wien's displacement law and Stefan-Boltzmann law that describe the spectral distribution and emission of blackbody radiation respectively.
Quantum mechanics is a new way of understanding the atomic world based on quanta or packets of energy. Light can behave as both a particle and a wave, with photons as quanta of light energy. The photoelectric effect and emission line spectra provided evidence that light behaves as quanta that can be absorbed or emitted in specific amounts of energy. Bohr's model of the hydrogen atom explained transitions between discrete energy levels by quantization of angular momentum and energy.
General Chemistry I - CHEM 181Critical Thinking Exercise.docxbudbarber38650
General Chemistry I - CHEM 181
Critical Thinking Exercise #3
Due Thursday, Oct. 24
Name_________________________
Section _______
Why do excited hydrogen atoms emit only specific wavelengths of light?
Introduction
In the 1800’s scientists discovered that a glass cylinder containing a low pressure of a gas will emit light when high voltage electricity is applied to metal electrodes inserted at opposite ends of the cylinder. This principal is used in fluorescent lighting today. When the light emitted by a particular gas, for instance hydrogen, was analyzed by passing it through a prism, scientists were surprised to find that only a few specific wavelengths of visible light were emitted, rather than a continuous range of wavelengths. This mystery took over 70 years to fully solve.
wavelength, (nm)
Infrared
Ultraviolet (uv)
Over time, scientists discovered that the wavelengths of radiation emitted by hydrogen extended from the ultraviolet through the visible into the infrared, microwave, and radio wave portions of the electromagnetic (EM) spectrum. There appeared to be a pattern in the wavelengths that consisted of a series of series of lines. The first 4 series starting from the shortest wavelength line are named for the people that discovered them.
In 1885 J.J. Balmer discovered a mathematical pattern in the wavelengths emitted by hydrogen in the visible and near ultraviolet regions of the electromagnetic spectrum:
Each allowed value for n plugged into this equation produces one of the wavelengths of light emitted by hydrogen in the region of the spectrum that Balmer studied.
Five years later another scientist, Johannes Rydberg, extended this equation so that it could predict all of the wavelengths emitted by hydrogen in all regions of the electromagnetic spectrum:
(eq. 1)
This equation contains two integers that must be greater than zero and the value of n must be greater than the value of m. The way it works is that the value of m specifies the series, e.g. m = 3 is necessary to generate the wavelengths observed in the Paschen series and n = 4,5,6… will generate the wavelengths emitted within that series. The constant R is known as the Rydberg constant.
Though the equations from Balmer and Rydberg demonstrated mathematical skill, they did not answer the big question on the minds of many scientists: Why do the atoms of hydrogen in the gas phase emit only certain wavelengths of radiation and why do the wavelengths have the pattern described by these clever equations. As it turned out, the solution to this riddle completely altered civilization on this planet.
Part I – Putting together pieces of the puzzle
Part of the reason that it took so long to solve hydrogen line spectrum puzzle was that scientists at the time had an incomplete understanding of light. Specifically, they were not aware of any relationship between the energy of light and the wavelength. It was assumed that the ene.
New Thermodynamics: A Superior Fit Revised Kinetic Theoryijrap
The accepted kinetic theory forms a basis for modern thermodynamics and is mathematically based upon equipartition and degrees of freedom. It remains plagued with the necessity of numerous degrees of freedom exceptions for it to explain both empirically determined heat capacities and adiabatic indexes. Furthermore, assuming kT/2 per degree of freedom is to accept that a gas molecule possesses a specified energy without providing any clarity concerning that energy’s origins. Energy without an origin contravenes the first law of thermodynamics. This author’s previously published superior fit kinetic theory will be clarified and elaborated upon. This includes showing that this revised kinetic theory is a superior fit to both known heat capacities and adiabatic indexes. Not only is it a superior fit that does not rely upon any exceptions, this author’s kinetic theory also provides insight into the actual sources of a gas molecule’s energy. Furthermore, clarity concerning the difference between isometric (isochoric) and isobaric heat capacities in terms of sensible work will be discussed, along withits likely empirical verification.
This document provides an overview of atomic structure and the development of atomic theory. It discusses early Greek philosophers' idea that matter is made of tiny particles and the contributions of scientists like Dalton, Thomson, Rutherford, and Millikan. Dalton established the basic atomic theory that all matter is made of atoms that cannot be divided. Rutherford's gold foil experiment led to the discovery of the nuclear model of the atom with a small, dense nucleus. The document also covers atomic and mass numbers, isotopes, atomic weights, and the periodic table.
This document contains an unsolved physics exam from 1995 containing 30 multiple choice problems. The problems cover topics in mechanics, thermodynamics, optics, electricity and magnetism, modern physics, and radioactivity. The full solutions are available online at www.vasista.net.
This document provides an overview of radiation heat transfer and outlines the course content for an undergraduate course on the topic. It discusses key concepts such as blackbody radiation, Planck's law, Stefan-Boltzmann law, and Wien's displacement law. Example problems are provided to illustrate calculating the spectral and total emissive power of blackbody radiation sources. The summary highlights that radiation transfer does not require a medium, occurs at the speed of light, and that surfaces behave as blackbodies when enclosed in an isothermal cavity.
Here, Modern Physics is explained very shortly and simply to make people understand that Physics is a very interesting subject to learn and modern physics is more interesting.
- The document discusses the structure of the atom, beginning with John Dalton's model of indivisible atoms and progressing to modern atomic structure based on experiments like Rutherford's gold foil experiment.
- It describes subatomic particles like electrons, protons, and neutrons that make up atoms, and models of atomic structure proposed by scientists like Thomson, Rutherford, Bohr, and Moseley.
- Key aspects of atomic structure covered include the Bohr model of electron orbits, calculation of orbital radii and velocities, and the relationship between potential energy, kinetic energy and total energy of electrons in atoms.
The document discusses various topics relating to stellar characteristics and evolution. It begins by explaining blackbody radiation and Wien's law, which show the relationship between an object's temperature and the wavelength of its peak emission. This allows astronomers to determine a star's surface temperature from its spectrum. The rest of the document discusses stellar classification schemes, the Hertzsprung-Russell diagram, the life cycles of different types of stars such as red giants and white dwarfs, and phenomena like supernovae, pulsars, and binary star systems. Spectral analysis provides insights into stellar physics and evolution.
MAHARASHTRA STATE BOARD
CLASS XI
PHYSICS
CHAPTER 1
UNITS AND MEASUREMENT
Introduction
The international system of
units
Measurement of length
Measurement of mass
Measurement of time
Accuracy, precision of
instruments and errors in
measurement
Significant figures
Dimensions of physical
quantities
Dimensional formulae and
dimensional equations
Dimensional analysis and its
applications
Chapter 2 - Mechanical Properties of Fluids.pptxPooja M
MARASHTRA STATE BOARD
CLASS XII
PHYSICS
MECHANICAL PROPERTIES OF FLUIDS
CONTENT
Density and pressure.
Buoyant force and Archimedes' principle.
Fluid dynamics.
Viscosity.
Surface tension.
MAHARASHTRA STATE BOARD
CLASS XI AND XII
CHAPTER 4
THERMODYNAMICS
CONTENT
Introduction
Thermal equilibrium
Zeroth law of
Thermodynamics
Heat, internal energy and
work
First law of
thermodynamics
Specific heat capacity
Thermodynamic state
variables and equation of
state
Thermodynamic processes
Heat engines
Refrigerators and heat
pumps
Second law of
thermodynamics
Reversible and irreversible
processes
Carnot engine
MAHARASHTRA STATE BOARD
CLASS XI AND XII
CHAPTER 5
OSCILLATIONS
CONTENT
Introduction
Periodic and oscillatory
motions
Simple harmonic motion
Simple harmonic motion
and uniform circular
motion
Velocity and acceleration
in simple harmonic motion
Force law for simple
harmonic motion
Energy in simple harmonic
motion
Some systems executing
simple harmonic motion
Damped simple harmonic
motion
Forced oscillations and
resonance
MAHARASHTRA STATE BOARD
CLASS XI and XII
CHAPTER 6
SUPERPOSITION OF WAVES
CONTENT:
Introduction
Transverse and
longitudinal waves
Displacement relation in a
progressive wave
The speed of a travelling
wave
The principle of
superposition of waves
Reflection of waves
Beats
Doppler effect
MAHARASHTRA STATE BOARD
CLASS XI AND XII
PHYSICS
CHAPTER 7
WAVE OPTICS
CONTENT:
Huygen's principle.
Huygen's principles & proof of laws of reflection/refraction.
Condition for construction & destruction of coherent waves.
Young's double slit experiment.
Modified Young's double slit experiment.
Intensity of light in Y.D.S.E.
Diffraction due to single slit.
Polarisation & doppler effect.
MAHARASHTRA STATE BOARD
CLASS XI AND XII
PHYSICS
CHAPTER 8
ELECTROSTATICS
Introduction.
Coulomb's law
Calculating the value of an electric field
Superposition principle
Electric potential
Deriving electric field from potential
Capacitance
Principle of the capacitor
Dielectrics
Polarization, and electric dipole moment
Applications of capacitors.
MAHARASHTRA STATE BOARD
CLASS XI AND XII
CHAPTER 9
CURRENT ELECTRICTY
CONTENT
Electric Cell and its Internal resistance
Potential difference and emf of a cell
Combination of cells in series and in parallel
Kirchhoff's laws and their applications
Wheatstone bridge
Metre bridge
Potentiometer – principle and its applications
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When a potential difference is applied across a conductor, the conduction electrons begin to drift in the direction of the applied electric field at a constant drift speed. This drift of electrons constitutes an electric current. Ohm's law establishes the direct proportional relationship between current and applied potential difference for many materials when their physical state remains unchanged. The proportionality constant is the resistance of the material.
CLASS XI - Chapter 9 optics (MAHARASHRA STATE BOARD)Pooja M
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- Reflection and refraction follow specific laws when light interacts with plane and curved surfaces. Multiple images can form when light reflects between two mirrors.
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CLASSXII (PHYSICS) Chapter 10 electrostaticsPooja M
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Here are the key steps to calculate the mass of Earth (M) from the given data:
1) Acceleration due to gravity on Earth's surface (g) = 9.81 m/s^2
2) Universal gravitational constant (G) = 6.67x10^-11 Nm^2/kg^2
3) Radius of Earth (R) = 6.37x10^6 m
4) Using the formula for acceleration due to gravity:
g = GM/R^2
5) Rearranging the terms:
M = gR^2/G
6) Substituting the values:
M = (9.81 m/s^2)(
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The document discusses various semiconductor devices including p-n junction diodes, rectifiers, special purpose diodes, bipolar junction transistors, and logic gates. It explains the working principles and applications of these devices. Rectification using half wave and full wave diode rectifiers is described to convert AC to DC. Special diodes like photodiodes, solar cells and LEDs are also covered. The common emitter configuration of a BJT and its use as an amplifier is explained. Finally, logic gates like NOT, OR, AND, NAND, NOR and XOR are defined along with their working principles.
This document discusses motion in two dimensions or motion in a plane. It covers topics like average and instantaneous velocity, acceleration, equations of motion with uniform acceleration, relative velocity, projectile motion, and uniform circular motion. Projectile motion involves calculating the maximum horizontal range of a projectile based on its initial velocity and acceleration due to gravity. Uniform circular motion requires both a tangential velocity and a centripetal force directed toward the center. The period, radius vector, angular speed, and centripetal acceleration are defined for uniform circular motion. Examples of motion in a plane include the trajectory of a projectile and the motion of a conical pendulum.
Temple of Asclepius in Thrace. Excavation resultsKrassimira Luka
The temple and the sanctuary around were dedicated to Asklepios Zmidrenus. This name has been known since 1875 when an inscription dedicated to him was discovered in Rome. The inscription is dated in 227 AD and was left by soldiers originating from the city of Philippopolis (modern Plovdiv).
This document provides an overview of wound healing, its functions, stages, mechanisms, factors affecting it, and complications.
A wound is a break in the integrity of the skin or tissues, which may be associated with disruption of the structure and function.
Healing is the body’s response to injury in an attempt to restore normal structure and functions.
Healing can occur in two ways: Regeneration and Repair
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This presentation was provided by Racquel Jemison, Ph.D., Christina MacLaughlin, Ph.D., and Paulomi Majumder. Ph.D., all of the American Chemical Society, for the second session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session Two: 'Expanding Pathways to Publishing Careers,' was held June 13, 2024.
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Certified as an ISO/IEC 27001: Information Security Management Systems (ISMS) Lead Implementer, Data Protection Officer, and Cyber Risks Analyst, Denis brings a heightened focus on data security, privacy, and cyber resilience to every endeavor.
His expertise extends across a diverse spectrum of reporting, database, and web development applications, underpinned by an exceptional grasp of data storage and virtualization technologies. His proficiency in application testing, database administration, and data cleansing ensures seamless execution of complex projects.
What sets Denis apart is his comprehensive understanding of Business and Systems Analysis technologies, honed through involvement in all phases of the Software Development Lifecycle (SDLC). From meticulous requirements gathering to precise analysis, innovative design, rigorous development, thorough testing, and successful implementation, he has consistently delivered exceptional results.
Throughout his career, he has taken on multifaceted roles, from leading technical project management teams to owning solutions that drive operational excellence. His conscientious and proactive approach is unwavering, whether he is working independently or collaboratively within a team. His ability to connect with colleagues on a personal level underscores his commitment to fostering a harmonious and productive workplace environment.
Date: May 29, 2024
Tags: Information Security, ISO/IEC 27001, ISO/IEC 42001, Artificial Intelligence, GDPR
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A Visual Guide to 1 Samuel | A Tale of Two HeartsSteve Thomason
These slides walk through the story of 1 Samuel. Samuel is the last judge of Israel. The people reject God and want a king. Saul is anointed as the first king, but he is not a good king. David, the shepherd boy is anointed and Saul is envious of him. David shows honor while Saul continues to self destruct.
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In this webinar, participants learned how to utilize Generative AI to streamline operations and elevate member engagement. Amazon Web Service experts provided a customer specific use cases and dived into low/no-code tools that are quick and easy to deploy through Amazon Web Service (AWS.)
Chapter wise All Notes of First year Basic Civil Engineering.pptxDenish Jangid
Chapter wise All Notes of First year Basic Civil Engineering
Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
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2. 2
Kinetic Theory of Gases and Radiation
1. Choose the correct option:
i) In an ideal gas, the molecules possess
(A) only kinetic energy
(B) both kinetic energy and potential energy
(C) only potential energy
(D) neither kinetic energy nor potential energy
ii) The mean free path λ of molecules is given by
where n is the number of molecules per unit volume and d is the diameter of
the molecules.
(A) √
2
𝜋 𝑛 𝑑2
(B)
1
𝜋 𝑛 𝑑2
(C)
1
√2 𝜋 𝑛 𝑑2
(D)
1
√2 𝜋 𝑛 𝑑
iii) If the pressure of an ideal gas decreases by 10% isothermally, then its volume
will _______.
(A) decrease by 9%
(B) increase by 9%
(C) decrease by 10%
(D) increase by 11.11%
iv) If a = 0.72 and r = 0.24, then the value of 𝑡𝑟 is
(A) 0.02 (B) 0.04
(C) 0.4 (D) 0.2
v) The ratio of emissive power of perfect blackbody at 1327°C and 527°C is
(A) 4:1 (B) 16:1
(C) 2:1 (D) 8:1
2. Answer in brief:
i) What will happen to the mean square speed of the molecules of a gas if the
temperature of the gas increases?
Ans: If the temperature of a gas increases, the mean square speed of the
molecules of the gas will increase in the same proportion.
ii) On what factors do the degrees of freedom depend?
Ans: The degrees of freedom depend upon
(i) the number of atoms forming a molecule
(ii) the structure of the molecule
(iii) the temperature of the gas.
iii) Write ideal gas equation for a mass of 7 g of nitrogen gas.
Ans:
3. 3
iv) If the density of oxygen is 1.44 kg/𝑚3
at a pressure of 105
N/𝑚2
, find the
root mean square velocity of oxygen molecules.
Ans:
v) Define athermanous substances and diathermanous substances.
Ans: Athermanous substances
Substances that don't allow transmission of infrared radiation through them
are called athermanous substances.
- For example, wood, metal, 𝐶𝑂2, water vapours, etc.
Diathermanous substances
Substances that allow transmission of infrared radiation through them are
called diathermanous substances.
- For example, rock salt, pure air, glass, etc.
3. When a gas is heated, its temperature increases. Explain this phenomenon on
the basis of the kinetic theory of gases.
Ans: Molecules of a gas are in a state of continuous random motion. They possess
kinetic energy. When a gas is heated, there is an increase in the average
kinetic energy per molecule of the gas. Hence, its temperature increases (the
average kinetic energy per molecule being proportional to the absolute
temperature of the gas).
4. Explain, on the basis of the kinetic theory of gases, how the pressure of a gas
changes if its volume is reduced at a constant temperature.
Ans: The average kinetic energy per molecule of a gas is constant at a constant
temperature. When the volume of a gas is reduced at a constant
temperature, the number of collisions of gas molecules per unit time with the
walls of the container increases. This increases the momentum transferred
per unit time per unit area, i.e., the force exerted by the gas on the walls.
Hence, the pressure of the gas increases.
4. 4
5. Mention the conditions under which a real gas obeys ideal gas equation.
Ans: A real gas obeys the ideal gas equation when the temperature is very high
and pressure is very low [Note: Under these conditions, the density of a gas is
very low. Hence, the molecules, on average, are far away from each other.
The intermolecular forces are then not of much consequence.]
6. State the law of equipartition of energy and hence calculate the molar specific
heat of monatomic and diatomic gases at constant volume and constant
pressure.
Ans:
5. 5
7. What is a perfect blackbody? How can it be realized in practice?
Ans: A perfect blackbody or simply a blackbody is defined as a body which absorbs
all the radiant energy incident on it. Fery designed a spherical blackbody which
consists of a hollow double-walled, metallic sphere provided with a tiny hole or
aperture on one side, Fig. The inside wall of the sphere is blackened with
lampblack while the outside is silver-plated. The space between the two walls is
evacuated to minimize heat loss by conduction and convection. Any radiation
entering the sphere through the aperture suffers multiple reflections where
about 97% of it is absorbed in each incidence by the coating of lampblack. The
radiation is almost completely absorbed after a number of internal reflections. A
conical projection on the inside wall opposite the hole minimizes the probability
of incident radiation escaping out.
When the sphere is placed in a bath of suitable fused salts, so as to maintain it at
the desired temperature, the hole serves as a source of black-body radiation. The
intensity and the nature of the radiation depend only on the temperature of the
walls.
6. 6
A blackbody, by definition, has a coefficient of absorption equal to 1. Hence, its
coefficient of reflection and coefficient of transmission are both zero. The
radiation from a blackbody, called blackbody radiation, covers the entire range of
the electromagnetic spectrum. Hence, a blackbody is called a full radiator.
8. State
(i) Stefan-Boltzmann law.
Ans:
(ii) Wien's displacement law
Ans:
9. Explain the spectral distribution of blackbody radiation.
Ans:
i. The rate of emission per unit area or power per unit area of a surface is
defined as a function of the wavelength λ of the emitted radiation.
ii. Scientists studied the energy distribution of blackbody radiation as a function
of wavelength.
iii. By keeping the source of radiation (such as a cavity radiator) at different
temperatures they measured the radiant power corresponding to different
wavelengths. The measurements were represented graphically in the form of
curves showing the variation of radiant power per unit area as a function of
wavelength λ at different constant temperatures as shown in the figure.
10. Prove Kirchhoff’s law of radiation theoretically.
7. 7
Ans: Consider an ordinary body O and perfectly black body B of the same
dimension suspended in a uniform temperature enclosure as shown in the figure.
At thermal equilibrium, both the bodies will have the same temperature as that
of the enclosure.
Let, E = emissive power of ordinary body O
Eb = emissive power of perfectly black body B
a = coefficient of absorption of O
e = emissivity of O
Q = radiant energy incident per unit time per unit area on each body.
Quantity of heat absorbed per unit area per unit time by body O = aQ.
Quantity of heat energy emitted per unit area per unit time by body O = E.
Since there is no change in temperature
E = aQ
Q = E/a .…(1)
Quantity of heat absorbed per unit area per unit time by a perfectly black body, B =
Q The radiant heat energy emitted per unit time per unit area by a perfectly black
body,
B = Eb
Since there is no change in temperature.
Eb = Q .…(2)
From equations (1) and (2),
11. Calculate the ratio of the mean square speeds of molecules of a gas at 30 K and
120 K.
Ans:
8. 8
12. Two vessels A and B are filled with the same gas where the volume, temperature,
and pressure in vessel A is twice the volume, temperature, and pressure in vessel
B. Calculate the ratio of the number of molecules of the gas in vessel A to that in
vessel B.
Ans:
13. A gas in a cylinder is at pressure P. If the masses of all the molecules are made
one-third of their original value and their speeds are doubled, then find the
resultant pressure.
Ans:
14. Show that rms velocity of an oxygen molecule is √2 times that of a sulfur dioxide
molecule at S.T.P.
Ans:
9. 9
15. At what temperature will oxygen molecules have same rms speed as helium
molecules at S.T.P.? (Molecular masses of oxygen and helium are 32 and 4
respectively).
Ans:
16. Compare the rms speed of hydrogen molecules at 127℃ with rms speed of
oxygen molecules at 27℃ given that molecular masses of hydrogen and oxygen
are 2 and 32 respectively.
Ans:
10. 10
17. Find the kinetic energy of 5 litre of a gas at STP given the standard pressure is
1.013 × 105
N/𝑚2
.
Ans:
18. Calculate the average molecular kinetic energy (i) per kmol (ii) per kg (iii) per
molecule of oxygen at 127°C, given that the molecular weight of oxygen is 32, R
is 8.31 J 𝑚𝑜𝑙−1
𝐾−1
and Avogadro’s number 𝑁𝐴 is 6.02 × 1023
molecules 𝑚𝑜𝑙−1
.
Ans:
11. 11
19. Calculate the energy radiated in one minute by a blackbody of surface area 100
𝑐𝑚2
when it is maintained at 227°C.
Ans:
20. Energy is emitted from a hole in an electric furnace at the rate of 20 W, when the
temperature of the furnace is 727°C. What is the area of the hole? (Take Stefan’s
constant σ to be 5.7 × 10−8
𝐽 𝑠−1
𝑚−2
𝐾−4
)
Ans:
12. 12
21. The emissive power of a sphere of area 0.02 𝑚2
is 0.5 kcal 𝑠−1
𝑚−2
. What is the
amount of heat radiated by the spherical surface in 20 seconds?
Ans:
22. Compare the rates of emission of heat by a blackbody maintained at 727°C and
at 227°C, if the black bodies are surrounded by an enclosure (black) at 27°C.
What would be the ratio of their rates of loss of heat?
Ans:
13. 13
23. The earth’s mean temperature can be assumed to be 280 K. How will the curve
of blackbody radiation look like for this temperature? Find out 𝜆𝑚𝑎𝑥. In which
part of the electromagnetic spectrum, does this value lie?
Ans:
24. A small blackened solid copper sphere of radius 2.5 cm is placed in an evacuated
chamber. The temperature of the chamber is maintained at 100 °C. At what rate
must energy be supplied to the copper sphere to maintain its temperature at 110
°C? (Take Stefan’s constant σ to be 5.67 × 10−8
𝐽 𝑠−1
𝑚−2
𝐾−4
and treat the
sphere as a blackbody.)
Ans:
14. 14
25. Find the temperature of a blackbody if its spectrum has a peak at (a) 𝜆𝑚𝑎𝑥 = 700
nm (visible), (b) 𝜆𝑚𝑎𝑥= 3 cm (microwave region) (c) λmax = 3 cm (FM radio
waves). (Take Wien’s constant b = 2.897 × 10−3
m K).
Ans: