61. Physics In physics, work is defined and measured as force x distance. is therefore measuredin terms of the work done + the energy lost as heat (available energy http://www.macalester.edu/biology/physics.html

Ten Important Concepts From the Physics The emergent property, "life", is created by a complex system of chemical and physical reactions. Physics identifies four primary forces in the universe: electromagnetism, gravity, and strong and weak nuclear forces. However, the forces that are the most important in understanding biological systems at the cellular level are electrical charge interactions (including hydrophobic and hydrophilic interactions), the forces of molecular collision, and the forces produced by macromolecular conformational change. Pressure is defined as force per unit of surface area (e.g. pounds per square inch) In cell biology, pressure is created primarily by molecular collision and is measured as osmotic, diffusion, or air pressure. However, the pressure produced by weight (mass x gravity) of fluid (hydrostatic pressure) or solid structures is a major component in understanding the physiology of multicellular creatures. In biology, pressure is traditionally expressed in millimeters of mercury (mmHg) or as osmotic pressure (particle concentration). These units can be interconverted. In physics, work is defined and measured as force x distance. This definition is useful, and can be expanded to aid our understanding of biological creatures at the cellular level. In cell biology, it is helpful to think of work as a) moving a molecular entity over a distance (e.g. molecules do work continually because they are in motion, greater force is required to concentrate than to diffuse molecules, thus work is done in the creation of concentration gradients); b) creating and/or degrading a molecular structure (much of the work of the cell does not involve the movement of anything, but rather produces molecular transformation, through chemical reactions and conformational changes.)

62. Heat And Energy Physics: Learn About Heat And Energy heat and energy physics Learn about heat and energy Available throughNetwork Educational Australia. Network Educational Australia http://www.network-ed.com.au/p/heatenergyphysics.htm

For the Best Prices and Widest Range of Software and Hardware at Educational and Retail Prices. MULTIMEDIA - MUSIC - VIDEO - BOOKS Freecall: Fax: 07 5576 5688 9 Ramly Drive, Burleigh Heads, Queensland 4220 - Australia Email: software@network-ed.com.au Website: www.network-ed.com.au Category: Classroom Software Subject: Science Suitability: Secondary Application: General Learning Heat and Energy Physics Platform: WIN Learn about Heat and Energy Containing 15 simulations: The Kinetic Model of Ideal Gases; (Gas Diffusion); Semi permeable Membrane; Maxwell’s Distribution; Brownian Motion; Isobaric Process; Isochoric Process; Isothermal Process; Adiabatic Process; Work of Gas; Specific Heat of Gas; Thermodynamic Cycles; Carnot Cycle; Evaporation and Condensation; and Isotherms of a Real Gas. Retail Further Licencing Information:

63. Advanced Physics Forums - Advanced physics Forums » Biophysics and PhysicalChemistry » heat, work and energy, go to bottom. http://www.advancedphysics.org/viewthread.php?tid=276

64. Re: What Causes Different Types Of Materials To Conduct Heat At Different Rates Steel Technical Center Area of science physics ID 884534502 solids, as well as thermalexpansion, heat content, etc. are based on how thermal energy is stored http://www.madsci.org/posts/archives/feb98/885153825.Ph.r.html

MadSci Network : Physics Re: What causes different types of materials to conduct heat at different rates Date: Fri Jan 16 16:23:47 1998 Posted By: Greg Dries, Senior Research Engineer,U. S. Steel Technical Center Area of science: Physics ID: 884534502.Ph Message: Library of Congress catalog card number is 66-16132. To begin with there are several different types of solid materials which are distinguished by how their atoms are arranged. Metals and ceramics Another type of solid, called plastics or polymeric materials , also do not have free electrons. Plastics also do not generally have an orderly atomic structure like ceramics and metals. Instead plastics can be thought of as a mixture of long molecules all chained and tangled together. Although the atoms in each molecule are tightly bonded to each other. There is little bonding between the different molecules, and no general order to the structure. The lack of an orderly structure in plastics contributes to it poorer thermal conductivity as you will see. Now given this knowledge of the structure of the different classes of solids, (metals, ceramics, and plastics), we will look at how heat energy is stored in solids. There are two main ways thermal energy is stored in solids. One way is in higher vibrational energy of the atom around its normal position and the other is in higher kinetic energy (or energy of motion) of any free electrons. In metals, heat energy is mostly transferred by the free electrons, which are free to easily move about the solid. This is why metals have the highest thermal conductivity. Here the thermal energy is picked up by the free electrons and rapidly transferred from atom to atom.

65. Fusion of physiology who became a distinguished researcher and physics professor, proposed solarradiation is the conversion of gravitational energy into heat 1 http://www.nobel.se/physics/articles/fusion/sun_1.html

I. The Age of the Sun How old is the sun? How does the sun shine? These questions are two sides of the same coin, as we shall see. The rate at which the sun is radiating energy is easily computed by using the measured rate at which energy reaches the earth's surface and the distance between the earth and the sun. The total energy that the sun has radiated away over its lifetime is approximately the product of the current rate at which energy is being emitted, which is called the solar luminosity, times the age of the sun. The older the sun is, the greater the total amount of radiated solar energy. The greater the radiated energy, or the larger the age of the sun, the more difficult it is to find an explanation of the source of solar energy. To better appreciate how difficult it is to find an explanation, let us consider a specific illustration of the enormous rate at which the sun radiates energy. Suppose we put a cubic centimeter of ice outside on a summer day in such a way that all of the sunshine is absorbed by the ice. Even at the great distance between the earth and the sun, sunshine will melt the ice cube in about 40 minutes. Since this would happen anywhere in space at the earth's distance from the sun, a huge spherical shell of ice centered on the sun and 300 million km (200 million miles) in diameter would be melted at the same time. Or, shrinking the same amount of ice down to the surface of the sun, we can calculate that an area ten thousand times the area of the earth's surface and about half a kilometer (0.3 mile) thick would also be melted in 40 minutes by the energy pouring out of the sun.

66. The Physics Of Everyday Stuff, By Sam Hokin goes into heat. The skid distance can be found by equationg the kinetic energy ofmotion to the work done by friction. Back to The physics of Everyday Stuff http://www.bsharp.org/physics/stuff/skidmarks.html

Skidmark Forensics An important task in auto accident recostruction is the analysis of skidmarks, which I call "skidmark forensics". Armed with data on the car's tires and the road surface, a accident reconstruction engineer can make a good estimate of a car's speed just before the driver hit the brakes. We can get the basic idea using a very simple model of friction. (Photo from The Traffic Accident Reconstruction Origin Sliding Friction A common model of friction comes from the observation that the heavier an object is, the harder it sticks to a surface. If you call the force you have to use to push a sliding object f , then the simplest model of friction that makes f increase with object weight is one that just says f is proportional to weight mg (where m is the mass of the car and g=9.8 coefficient of kinetic friction , and accident investigators have tables for all sorts of tires and road surfaces. So how long is a skidmark for a given initial car speed? There are a couple ways of figuring this out. I'll use an energy technique here. The main idea is this: the car is hurtling along at speed v , which means it has a lot of kinetic energy of motion associated with it. If the car has mass

67. Physics Relativistic energy, Mass and Momentum. Mechanical Properties of Materials Stateof Matter, Solids, Fluids, Gases. Thermal physics Temperature, heat, Thermal http://www.iinf.polsl.gliwice.pl/metakier/physics.html

Lecturer: Jacek SZUBER Course-No Semester Course type Lectures + classes + laboratories Hours / week Teaching methods lectures, simple calculations, practical works Status of the course in the study program Obligatory Prerequisites Teaching aids C.O'Sulivan Understanding Physics J.Wiley and Sons, Inc., New York, 1998 Examination method written examination combined with conversation Course description A. LECTURES Understanding of the Physical Universe: Physics Methodology. Simple Motions: Fundamentals of Dynamics - Force, Momentum and Impulse. Motion in Three Dimensions. Making Think's Happened: Energy and Power. The Conservation of Energy. Potential Energy. Conservative Fields. Many Body Interactions. The Principle of Conservation of Momentum. Rigid-Body Dynamics: Conservation of Angular Momentum and Energy of Rigid Bodies. Relative Motion: Inertial and Non-Inertial Frames, Coriolis Force. Special Relativity: Foundation, Universal Speed Limit, The Principle of Relativity and Consequences, Relativistic Energy, Mass and Momentum. Mechanical Properties of Materials: State of Matter, Solids, Fluids, Gases. Thermal Physics: Temperature, Heat, Thermal Radiation, Thermal Expansion. Thermodynamics:

68. Lesson 10.2 Heat And Thermal Energy KE, but some individual molecules can have more energy than others it needed to getrid of some excess heat (probably caused by studying physics too hard http://titans-web.s716.ips.k12.in.us/~blachlym/pol/unit_10/10-02.htm

Unit 10: The Physics of Heat Lesson 2: Heat and Thermal Energy In this lesson: Objectives: Introduction Physics in the News Defining Temperature Thermal Energy ... An application: Evaporation When you have completed this lesson and the homework, you will be able to: understand the terms heat, temperature, thermal energy and internal energy understand that heat is the flow of thermal energy understand that temperature is a measure of the internal energy of a body. Textbook Correlation Ch. 10, Section 1 Introduction We often associate heat with temperature, but seldom do we think about what it these two terms really mean. For example, which has a higher temperature: A steaming cup of tea or a huge iceberg? The answer is obvious the tea is at a higher temperature. But which of the two has more heat? The iceberg does, but who would have thought that? To understand why an iceberg has more heat, we need to take a closer look at the physics of heat and try to understand what is happening at the molecular level. Physics in the News The following is an article that appeared in a recent issue of a scientifically oriented periodical. It will help lay the groundwork for our discussions this chapter.

69. Lab H Conversion Of Electrical Energy To Heat Energy Lab H Conversion of Electrical energy to heat energy Object. Data Analysis.1. Calculate the electrical energy used to heat the water in joules. http://physics.njit.edu/classes/physlab/laboratory231/labH/labH.html

Lab H Conversion of Electrical Energy to Heat Energy equipment Object To determine the conversion factor between the electrical energy unit, the joule, and the heat energy unit, the calorie. Theory The rate heat is developed in a resistor is P = I*V where P is the power in watts, I, the current in amperes, V, the potential difference in volts across the resistor R in ohms. If this energy goes into heating water, the rate at which the water is heated, dQ/dt, is where dm/dt is the rate at which water flows past the resistor and is heating, D t is the rise in temperature and c is the specific heat of water. In this equation the units are: value units dm/dt g/s c cal/g o C DT o C or Kelvins dQ/dt cal/s where one calorie is the amount of heat energy needed to raise one gram of water one degree Celsius at 4 o C. In the steady state, dm/dt and therefore dq/dt will be considered constant. Procedure: 1. Set up the apparatus as shown in Figure 1. DO NOT TURN ON THE POWER. 2. Adjust the water flow to about 1.5 cc/s 4. Read the input and output temperatures. Allow the system to reach a steady state.

70. Lab G Conversion Of Mechanical Energy To Heat Energy Lab G Conversion of Mechanical energy to heat energy equipment Object.To determine the conversion factor between the mechanical http://physics.njit.edu/classes/physlab/laboratory231/labG/labG.html

Lab G Conversion of Mechanical energy to Heat Energy equipment Object To determine the conversion factor between the mechanical energy unit, the joule, and the heat energy unit, the calorie. Theory Work done by friction forces acting on a body or system of bodies results in the generation of energy, i.e., the mechanical wok done by the force of friction is converted to heat. When a constant frictional force torque acts on a rotating body the work done is W = G f Q where G f is the torque and Q , the angle through which the body turns. In this experiment, the frictional torque is applied to a rotating disc by a force acting tangent to the disc perimeter. Thus W = FR Q where F is the applied force in Newtons, R , the radius in meters, Q , the angle in radians, and W is in Joules. The heat Q added to a body of mass m which rises in temperature an amount D T is Q = mc D T where c is the specific heat of the body. If m is in grams, D T in o C and c in cal/g o C , then Q will be in calories. One calorie is the amount of heat needed to raise one gram of water one degree Celsius at 4 o C.

71. PH1110 College Physics I Thermal physics. 1. Temperature and heat Temperature and temperature scales; TheKelvin scale; Thermometers; Thermal expansion; heat and internal energy; Specific http://www.phy.mtu.edu/curriculum/PH1110.html

PH1110 College Physics I ... (3,0,0) f, s ... 3 Cr An overview of basic principles of kinematics, dynamics, elasticity, fluids, heat, thermodynamics, mechanical waves, and interference and diffraction of mechanical waves. Prerequisites: ; and MA1032 or MA1033 or MAT1115 This course is a prerequisite for: FW2052, FW5090, MET2000, MET3250, and Course fee: $8.50 Physics, 6 th Edition Typical Syllabus Mechanics 1. Introduction and Mathematical Concepts The nature of Physics Units The role of units in problem solving Trigonometry Vector addition and subtraction The components of a vector Addition and subtraction using components 2. Kinematics in one dimension Position and displacement Speed and velocity Acceleration Equations of kinematics for constant acceleration 3. Kinematics in two dimensions Projectile motion Relative motion 4. Forces and Newton's laws Force and mass Newton's first law Newton's second law Vector nature of the second law Newton's third law Gravitational force Weight Normal force Static and kinetic friction Tension Equilibrium applications Nonequilibrium applications 5. Dynamics of Uniform Circular Motion

72. PH3300 MTU Physics Course Description and Thermal physics (Reif) Thermal physics (Kittel and the First Law of Thermodynamics(2) Work and heat; Adiabatic work; Internal energy and heat Capacity; The http://www.phy.mtu.edu/curriculum/PH3300.html

PH3300 Thermodynamics and Statistical Mechanics ... (3-0-0) s ... 3 Cr Thermodynamic systems, heat, work, laws of thermodynamics, formal mathematical relations, cycles, phase equilibrium, and multicomponent systems. Elementary kinetic theory. Introduction to microscopic view of entropy, ensemble theory, and applications of statistical mechanics. Prerequisite: This course is a prerequisite for Text (Spring 2004): Thermal Physics , Ralph Baierlein (ISBN 0-521-59082-5) Previous Text: An Introduction to Thermal Physics , Daniel V. Schroeder (ISBN 0-201-38027-7) Typical Text: Heat and Thermodynamics, 7 th Ed ., Zemansky and Dittman. Reference Texts: Statistical and Thermal Physics (Reif) Thermal Physics (Kittel and Kroemer) Typical Syllabus (Approximate # of Lectures) I. Thermodynamics Microscopic versus macroscipic Scope of thermodynamics Importance of thermodynamics 2. Temperature and the Zeroth Law of Thermodynamics (1) Concept of Temperature Measuring Temperature Ideal-Gas Temperature 3. Simple Thermodynamic Systems (2) Equilibrium Equation of State Differential relations 4. Work (1)

73. Physics Concept Map, Programmable physics Concept Map, Programmable (c) edorsz 198486. 14, heat, watt / m^2 power per unit area heat light energy flux flux U, -3, o, 1, http://helios.acomp.usf.edu/~edorsz/

Physics Concept Map Physics Concept Map, Programmable (c) edorsz 1984-86 Learn to understand science concepts and solve equations, using simple arithmetic, and user-friendly color coding. aaaScrap.rtf If Concept Map does not appear above, then press here Entities Table time m*t_:_mass*tim energy or work Q : e_charge length gravity jerk density Q * t_:_ch * time hgrum areaMassDens LI*Q_:_ind*Q acceleration linearMassDens G ( mass) specificHeat moment Sbc G ( general) momentOfInertia abs-,dyn-visc'y phie :eFluxS flux radiance momentum MassTmp/Time Q / M flux*length G ( energy) Q / N velocity or u mole or N Sbc*Length power H : magFldStrng Sbc*area mass absVisFx_G( mfr) Ltcg: LaPlaceCG Sbc*area*T2 R/M_:_res / Mas heat or flux U G ( momentum) Ltcg*L5 thco_:_-ance pressure or stress capacitivity force dS or R Symbols Table second or s or t kg * t newton or N or U kelvin or T coulomb or Q farad * m^2 meter or m kg / m^4 N * m^2 / kg^2 T / t ampere = Q / t henry / m m / t^3 kg / m^3 joule * meter T * t coulomb * t henry watt / kg kg / m^2 kg /( t * m^4) T * m coulomb / m^3 henry * coulomb m / t^2 kg / m kg /( t * m^3) joule /( kg * T) coulomb / m^2 volt / m N * m^2 / kg kg * m kg /( t * m^2) watt /( m^2*T^4) coulomb / m volt 1 /( m^3 * t) kg * m^2 kg /( t * m) watt /( m^2 * T) coulomb * m volt * m 1/ ( m*2 * t) watt / m^4 N * t kg * T / t coulomb / kg weber / m 1/ ( m * t) watt / m^3 joule * t watt /( T * m^3) coulomb / N ohm m / t watt / m mol or N watt /( m * T^4) ampere / m^2 weber joule * t / kg watt = joule / t N * m^2 watt /( T * m) ampere / m ohm * m m^3 / t joule / m^6 g / N watt / m^4 ampere * m weber * m

74. S C O R E Science - Grades 9-12 Physics Standards Grades 912 physics Content Standards. c. thermal energy (commonly called heat) consistsof random motion and the vibrations and rotations of atoms and http://scorescience.humboldt.k12.ca.us/fast/teachers/content/hsphys.htm

Grades 9-12 Physics Content Standards "Standards without asterisks represent those that all students are expected to achieve in the course of their studies. Standards with asterisks represent those that all students should have the opportunity to learn." Motion and Forces 1. Newton's laws predict the motion of most objects. As a basis for understanding this concept, students know: a. how to solve problems involving constant speed and average speed. b. when forces are balanced no acceleration occurs, and thus an object continues to move at a constant speed or stays at rest (Newton's First Law). c. how to apply the law F=ma to solve one-dimensional motion problems involving constant forces (Newton's Second Law). d. when one object exerts a force on a second object, the second object always exerts a force of equal magnitude and opposite direction. (Newton's Third Law). e. the relationship between the universal law of gravitation and the effect of gravity on an object at the surface of the Earth.

75. A Physics Lesson Learned The Hard Way Everyone should remember these basic principles of physics from high school involvesa conversion of the vehicle s kinetic energy into heat energy from the http://www.safetycenter.navy.mil/media/seashore/issues/spring04/physicslesson.ht

Media Divisions Media home Approach Ashore Fathom ... Mech New! Dive Safety Lines Ships' Safety Bulletin FLASH Safety Posters Popular Approach Vault Mech Vault Submit an Article What's Your Call Sign ... Writing 101 Other Services Acquisition Safety Contact Us Checklists Downloads ... Spring 2004 A Physics Lesson Learned the Hard Way By LCdr. Jesse Brittain A moored fuel barge needed to be moved about 60 feet down a pier so other operations could occur. Personnel lifted the pier-side eyes of the mooring lines and used a workboat to give the barge a shove to get it moving in the desired direction. When the barge reached the desired position, the workers placed the eyes of the lines over pier cleats to stop and hold the craft in place. Unfortunately, two of the lines failed, hitting and injuring a person on the pier. The victim spent five days in a hospital but is expected to make a full recovery. Everyone should remember these basic principles of physics from high school: Energy neither can be created nor destroyed—just converted in form (the first law of thermodynamics).

76. Physics 250 - Summary For Final Exam physics 250 Summary for Final Exam. energy is conserved (change insystem s internal energy equals heat in minus the work done). http://niuhep.physics.niu.edu/~willis/phys250/final_summary.htm

Physics 250 - Summary for Final Exam These are what I consider to be the core ideas within each chapter. Mostly I am just listing the ideas and not explaining them; you will have to go to the text for the details. The final exam will have 15 multiple choice and 5 worked problems; expect 1 multiple choice per chapter. Chapter 1 : Introduction and Mathematical Concepts vector addition and subtraction; vector components Chapter 2 : Kinematics in One Dimension constant acceleration: variables are initial speed, final speed, displacement, acceleration, and time. Given any three, find the other two. Chapter 3 : Kinematics in Two Dimensions do x and y components separately; time is the same for both Chapter 4 : Forces and Newton's Laws of Motion F = ma; F and a are both vectors examples of forces: gravitational, normal, frictional, tension equilibrium: sum of forces is zero non-equilibrium: sum of forces is mass times acceleration Chapter 5 : Dynamics of Uniform Circular Motion centripetal acceleration and force Chapter 6 : Work and Energy work is force times distance work done by net force equals change in kinetic energy potential energy power is the rate at which work is done energy is conserved Chapter 7: Impulse and Momentum force times time is change in momentum momentum is conserved Chapter 8 : Rotational Kinematics define rotational displacement, velocity, and acceleration; then equations of motion are the same as linear ones

77. Symbols And Abbreviations Q, heat (energy). W, Watts* (power = J / s), weight (force), work (energy). funny(or you just want to know where you are!), see the College physics for Students http://www.rwc.uc.edu/koehler/biophys/symb.html

Symbols and Abbreviations Units are denoted by an asterisk. Dimensions and values of constants are in parentheses. See also the NIST pages on constants, units and uncertainty a, A acceleration (length / time atomic mass (total number of protons and neutrons in an atom) A Amperes * (electric current = C / s), Angstroms* (length = 10 m), amplitude (length) b intercept of a linear graph, drag coefficient (mass / time) B magnetic field (force / current) c speed of light (2.998 x 10 m / s), specific heat (energy / mass x temperature), concentration (number / volume), speed of sound cal calories * (energy = 4.186 J) cc cubic centimeter c g group velocity c p phase velocity C Celsius* (temperature), Coulombs * (electric charge), capacitance (charge / electric potential), heat capacity (energy / temperature), concentration Cal kilocalories * (energy) Ci Curie * (unit of radiation, equivalent to 3.7 x 10 decays / s) d distance D diffusion constant (area / time) db decibels (relative intensity) e electron, charge of an electron (1.602 x 10 C) eV electron Volts * (energy = 1.602 x 10

78. College Physics For Students Of Biology And Chemistry - Heat Flow The temperature of a substance changes as heat energy is added to it. running, 2510.Approximately 80 % of the energy used by your body ends up as waste heat. http://www.rwc.uc.edu/koehler/biophys.2ed/heat.html

Heat Flow Heat (denoted by Q) is thermal energy : the energy of a system of particles randomly colliding with each other and objects in their environment. It has dimensions of energy, but it is NOT a state variable : unlike temperature, its value does depend on the past history of the system. For instance, a system can be isothermally expanded by adding heat, or its pressure can be slowly decreased without the addition of heat. Yet the final pressure, temperature and volume are the same. The temperature of a substance changes as heat energy is added to it. The heat capacity (denoted by C) of an object is the ratio of change in heat to change in temperature, and the specific heat (denoted by c) of a substance is the heat capacity per unit mass. We therefore have D Q = m c D T. Some useful specfic heats are: water 4.186 kJ / kg K ice water vapor human tissue air Ice and water vapor (steam) are alternate phases of water. For a given substance at a given pressure, phase changes occur at well-defined temperatures. For water at standard atmospheric pressure (at the surface of the earth), those are 273.15K and 373.15K: C and 100C, the freezing and boiling points, which define the Celsius degree, and therefore the Kelvin . For a given substance, the heat change per unit mass required for a

79. PHYSICS 132 -- CHAPTER 22 physics 132 Notes on Chapter 22. `heat is a verb, as in ``to heat . It meansto add to the energy of molecular motions of a body by molecular transfer http://www.physics.nmt.edu/~raymond/classes/ph132-s04/studynotes/ch22.html

Physics 132 Notes on Chapter 22 This chapter is mostly quite straightforward. It begins with a discussion of the empirical meaning of temperature. This section also introduces the idea of thermal expansion. ``Heat'' is a verb, as in ``to heat''. It means to add to the energy of molecular motions of a body by molecular transfer processes such as heat conduction or absorption of radiation. ``Specific heat'' is the amount of heating needed to raise the temperature of a body of unit mass by one degree. The first law of thermodynamics states that the change in internal energy (i. e., energy of molecular motion) of a body is equal to the heat added to the body minus the work done by the body. It is really a statement of the conservation of energy. Heat conduction in a solid body obeys a simple law given in the text. Thermal radiation is electromagnetic radiation emitted by the acceleration of charged particles which are undergoing ordinary thermal motions. The energy per unit area per unit time emitted by a body depends on the body's emissivity and its temperature. If the emissivity is epsilon, which ranges from to 1, then the body has a reflectivity 1 - epsilon. Black body radiation occurs in a cavity where the walls are all the same temperature. This depends only on temperature and not on the emissivity of the walls. Friction occurs when two bodies rub against each other. Friction between solids depends on the force holding them together and on the coefficient of friction. Be sure to understand the difference between static and kinetic friction. Friction between bodies separated by a thin sheet of fluid depends on the shear in the fluid and the fluid's viscosity.

80. Thermal Physics Unit 2 - Heat Thermal physics Unit 2 heat. Units. heat is a form of energy - thedisordered kinetic energy of the molecules of a body. heat energy http://www.shef.ac.uk/physics/teaching/phy001/unit2.html

Thermal Physics Unit 2 - Heat Units Heat is a form of energy - the disordered kinetic energy of the molecules of a body. Heat energy is therefore measured in the usual unit of energy, the Joule J . The rate of heat flow is measured in J s or Watt s W . These are the units we will use in this course. However, before the relationship between heat and other energy was understood, special units were used, and these are still in use today. a) The calorie [b) The mean calorie c) 1 kilogram-calorie or kilocalorie = 1000 calories. 1 calorie = 4.186 J 1 kilocalorie (often written C alorie!!) = 4186 J Specific Heat The specific heat c , of a substance is equal to the quantity of heat which must be supplied to unit mass of the material to increase its temperature by 1 degree with no change of state. Therefore where Q is the quantity of heat, m is the mass of the body and T the temperature change. or Q m c T The units of specific heat are J kg K (or cal g The heat capacity or thermal capacity of an object is the quantity of heat which must be supplied to it to raise its temperature by 1 degree. Its units are J K . If the mass of the object is m obj and its specific heat c obj , then the thermal capacity is simply equal to m obj c obj Another term you might meet is the water equivalent of an object. This is the mass of water with the same heat capacity as the object.

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