Class Note for NATS 101 at UA 2
Class Note for NATS 101 at UA 2
Popular in Course
Popular in Department
This 55 page Class Notes was uploaded by an elite notetaker on Friday February 6, 2015. The Class Notes belongs to a course at University of Arizona taught by a professor in Fall. Since its upload, it has received 51 views.
Reviews for Class Note for NATS 101 at UA 2
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 02/06/15
The Next Piece in the Puzzle to Understand Global Changes In this house we OBEY the laws of thermodynamics HOmer Simpson 751 if KE or KinE energy of motion orthe ability of a mass to do work a PE energy a system I pesSesses if it is capable of doing i work but is not doing work now 3 j def the grand total of all energies inside a substance a measure of the quantity of 55quotcontained in every object in 7 i Thermal Energy Atoms and molecules are constantly jiggling in some sort of backandforth vibratory motion The greater this molecular kinetic energy is in a substance the hotter the su bstance is TH E RMODYNAMICS def The study of the general I re erties of ENERGY Thermal energy la 3 a central role in understanding these properties hence the study of energy can also be called thermodynamics Remember vibrating molecules Rotation Vibration quotIf tells how warm or cold a body is with respect to some standard eg Fahrenheit F Celsius C or Kelvin K standard scales 39 Temperature is a g quot eg water vapor molecule H20 at lower temperature Thermal Energy When atoms and molecules cool so much that they lose all their kinetic energy they reach the quotabsolute zeroquot of temperature 27315 459690F 0 Kelvin Review p 57 Thermal Energy In which direction will THERMAL ENERGY be transferred I A hot box of gas and a cold box a gas at the instant they are ut into contact Most of the molecu es in the hot box move rigidly while most of the molecules in move slowly 1 cold box the thermal energy that is from one body to another because of a temperature difference Higher T Lower T Intermediate temperature It A at there has been time for the ho box to warm up the cold box the molecules in the lefthand box have slowed down while those in the righthand box have sped up THE FIRST LAW OF THERMODYNAMICS stated as the Law of Conservation of Energy Energy can be transformed Changed from 39one form to another but the total amount always remains the39 same G E rav 4 impaCt Energy flow for a falling book with air resistance FIRST LAW OF THERMODYNAMICS another wa of sa in it In an isolated system the total amount of energy including heat energy is conserved although energy may change from one form to anorner over and over again stated as the Law of Heating Thermal energy ows spontaneoust without external assistance from a higher temperature object to a lo wertemperature object that Energy of all kinds in our material world disperses or dissipates if it is not hindered from doing so ier how much energy has flowed from pemg constricted or concentrated to being more widely spread out at the temperature of the process httpiersevuoreqoneduvlabThermodvnamicsindexhtml at the moleCUIar level When a box of hot gas amp cold gas are allowed to mix eventually the faster molecules striking the slower molecules Spread out some of their energy to the slower molecules leadinv to a wider ran39e of speed and an intermediate temperature in the box The second law of thermodynamics is a powerful aid to help us understand why the world works as it does why hot pans cool down why our bodies stay warm even in the cold why gasoline makes engines run Hi temperature oh B 8 g 3 5 E5 lawtemperature object r Once a system creates thermal energy that system will never by itself spontaneously be able to return to its previous condition There is an reesut about any process that creates thermal energy But toda in order to et out of Class early just answer the questions on your own outside of Class right here in the CLASS FOLLOWUP 1 From the cold beer can into Homer s warmer beer belly From Homer s beer belly to the colder beer can From BOTH the beer can to Homer Homer to the beer can 1 From the cold beer can into Homer s warmer beer belly From Homer s beer belly to the colder beer can From BOTH the beer can to Homer Homer to the beer can temperature To prepare for the next few CLASS SELF TEST QUESTIONS some background is neededr so BEFORE PROCEED39ING READ pp 5758 in CLASS NOTES on Unit of Measure of Thermal Energy ie the joule or calorie Specific Heat Heat Capacity Change of Phase ie Latent Energy LE amp Sensible Heat H Heat Transfer Thermal Energy Units Unit for Thermal Energy the joue or calorie Low Joule Cola A CALORIE is the amount of thermal energy required to change the temperature of 1 gram of water by 1 C specifically from 145 to 155 C one gram of water is roughly equivalent to the weight of one cubic centimeter of water the amount of 7 V l 39 L 39 quot1 required to raise1 gram of roemeternperature water 1 degree Celsius in temperature Other Important Terms speCIrICHeat the amount of thermal energy in calories required to raise the temperature or 1 gram or any sunsrance by 100 m we r a v density of a substance for a given volume Density is measured in grams per cubic centimeter z represents the capacity of a substance to absorb heat in relation to its volume and aensrty Substance Specific Heat Heat Capacitv cal joules water 100 4186 100 air 024 1005 000024 000034 concrete 021 879 050 sand 020 837 010 060 higherifwe39t rock 0185 774 iron 0105 440 082 silver 0056 234 059 1 WATER 2 AIR 3 SAND gtI39Ol anSW r Check out t h ek he kt C paCIIIeS In Ine table on p 57 of Class Notes 1NATER 2 AW 3 SAND Q3 a U J mm mgg g gigwjm mg W22 MUM allovlkg fi mm mm 5 mg mgam mpgmmrg 2 E Mm Iliade sm aw mpgmmme mm mm 3 E m tmm tangy Wm mm mm up at lm swim raw Q3 ca W lfogt1 Mm m m gs mmm we WW 1 ake ib xs t a i FURLST Hm 8 mg mam gmpgramm 2 a rm mam sw f mg m mm may mm 3 a mi harg mgy Wm mm Mat up at th samg mtg mam h1 m if m mm w 2S muw H v H t 7 W frff w h fnnng will hold the thermal energy longer 5 tLV xi i7l7eth fnnng will heat up faster and to a much higher temperature than the crust will vat hvfffft h fnnng will hold the thermal energy longer quotadueagtgt g e mx J eie5l7lth fnnng will heat up faster and to a much higher temperature than the crust will 7am mug am Ezw ZAEz EE CNN w w g 0 mggmmgg o ggg agggggwg m 6252 g 3 Eggwgggg gggagggggw WHY When the temperature of the substance is increased the molecules jiggle faster and the more energetic collisions between the molecules force them to move farther apart thus expanding the substance and making it less dense These thermal differences play an important rolein driving httpwww coloradoed uphvsicsZOOObeCtem peratu re html THERMODYNAMICS amp PHASE CHANGES IN H20 Energy stored as LATENT ENERGY energy is hidden amp not sensed ENERGY l5 ABSORBED WHEN CHANGE OF STATE IS IN THIS DIRECTION EN ERG IS RELEASED WHEN CHANGE OF STATE IS IN THIS DIRECTION L Energy released as SENSIBLE HEAT ie the warmth can be sensed PHASE CHANGES another view Energy absorbed g Sublimation Memng Evaporation Liquid liquid water an lt Freezing Condensation Deposition 9 Energy released See Fig 423 p 76 in SGCKump text Vuporizing E q 540 is u g 2 E q a S 6 o Hea r m calories z we VAPORIZING 43 39u g I u l at a I I w 0 0239 0 x I i g L so CAL 100 CAL 4 540 CAL391 500 e I 1 HEAT IN CALORIES Q6 Which segment or segments of the graph represents SENSIBLE HEAT H 1xampz 3Yonly 2Xonly 4Zonly z mo VAPORIZING 43 I l I l I l I TEMPERATURE IN C x l L ao cALT 100 CAL 4 540 CAL1 l l I LJ I I I HEAT IN CALORIES a U o I Q6 Which segment 5 of the graph represent SENSIBLE HEAT H 1xampz 3Yonly 2Xonly 4Zonly Q In a phase change from ice to water or water to water vapor WHAT is absorbing the energy 1 the surrounding environment 2 the H20 molecules 3 both the environment amp the H20 Energy is absorbed when change of phase is in this direction 22 Energy is released when change of phase is in his direction lt Q In a phase change from ice to water or water to water vapor WHAT is absorbing the energy 1 the Surrounding environment 2 the H20 molecules 3 both the environment amp the H20 Energy is absorbed when change of phase is in this direction 22 Energy is released when change of phase is in his direction lt 08 In a phase change from water vapor to water or water to ice nu WHERE is the energy being released 1 into the surrounding environment 2 into the H20 molecules 3 into both the environment amp the H20 Energy is absorbed when change of phase is in this direc on 22 Energy is released when change of phase is in his direc on lt 08 In a phase change from water vapor to wateror water to ice nu WHERE is the energy being released 1 into the surrounding environment L I I ILU Ll I6 I I20 mOIeCUIeS 3 into both the environment amp the H20 Energy is absorbed when change of phase is in this direc on 22 Energy is released when change of phase is in his direc on lt ltltIgtu 0372mm ICINRVPZWM 9301536 Emirzo mszm m mrmbywm EImZ DI me O m4gt4m m 7 Jim ONm OZ a L m n r U T m E U m n T llr Imgn 3 DEHACamm HEAT TRANSFER the process by which thermal energy moves from one place to anothe Convection j Conduction Pan in Contact with burner 7 h 7 in y Radiation V Electromagnetic Wave 39 is not heat energy It does not become heat jiggling molecules KEY CONCEPT The sun39s energy comes in as radiant electromagnetic energy quot i v p quot eg by the surface of the earth a gas in the atmosphere etc Got it all down Homer If not ask a NAT S 101 GO student
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'