Physics 121: Lecture 24 Today's Agenda Announcements About midterm 2: next Tuesday Covers Chap 6-13 Homework 10: due Friday Dec 2@ 6: 00 PM Chap.10:#2,22,24,28,34,42,49,55,and58 Chap.11:#2,9,13,27,30,34,and43 Today's topiCs Temperature and zeroth law of thermodynamics Temperature scales and thermal expansion Ideal gas Heat and energy Laws of thermodynamics Physics 121: Lecture 24, Pg
Physics 121: Lecture 24, Pg 1 Physics 121: Lecture 24 Today’s Agenda Announcements About midterm 2: next Tuesday Covers Chap. 6 - 13. Homework 10: due Friday Dec. 2 @ 6:00 PM. Chap. 10: # 2, 22, 24, 28, 34, 42, 49, 55, and 58. Chap. 11: # 2, 9, 13, 27, 30, 34, and 43. Today’s topics Temperature and Zeroth Law of Thermodynamics Temperature scales and thermal expansion Ideal gas Heat and energy Laws of thermodynamics
Chap. 13: Temperature Temperature: measure of the motion of the individual atoms and molecules in a gas liquid or solid related to average kinetic energy of constituents High temperature: constituents are moving around energetically In a gas at high temperature the individual gas molecules are moving about independently at high speeds In a solid at high temperature the individual atoms of the solid are vibrating energetically in place The converse is true for a"cold"object In a gas at low temperature the individual gas molecules are moving about sluggishly There is an absolute zero temperature at which the motions of atoms and molecules practically stop There is an absolute zero temperature at which the classical motions of atoms and molecules practically stop Physics 121: Lecture 24, Pg 2
Physics 121: Lecture 24, Pg 2 Chap. 13: Temperature Temperature: measure of the motion of the individual atoms and molecules in a gas, liquid, or solid. related to average kinetic energy of constituents High temperature: constituents are moving around energetically In a gas at high temperature the individual gas molecules are moving about independently at high speeds. In a solid at high temperature the individual atoms of the solid are vibrating energetically in place. The converse is true for a "cold" object. In a gas at low temperature the individual gas molecules are moving about sluggishly. There is an absolute zero temperature at which the motions of atoms and molecules practically stop. There is an absolute zero temperature at which the classical motions of atoms and molecules practically stop
Heat Solids, liquids or gases have internal energy Kinetic energy from random motion of molecules translation rotation vibration At equilibrium, it is related to temperature Heat: transfer of energy from one object to another as a result of their different temperatures Thermal contact: energy can flow between objects Physics 121: Lecture 24, Pg 3
Physics 121: Lecture 24, Pg 3 Heat Solids, liquids or gases have internal energy Kinetic energy from random motion of molecules translation, rotation, vibration At equilibrium, it is related to temperature Heat: transfer of energy from one object to another as a result of their different temperatures Thermal contact: energy can flow between objects T1 T2 U1 U2 >
Zeroth Law of Thermodynamics Thermal equilibriun when objects in thermal contact cease U heat transfer same temperature If objects a and B are separately in thermal equilibrium with a third object C, then objects a and b are in thermal equilibrium with each other C A B Physics 121: Lecture 24, Pg 4
Physics 121: Lecture 24, Pg 4 Zeroth Law of Thermodynamics Thermal equilibrium: when objects in thermal contact cease heat transfer same temperature T1 T2 U1 U2 = If objects A and B are separately in thermal equilibrium with a third object C, then objects A and B are in thermal equilibrium with each other. A C B
Temperature scales Three main scales Farenheit Celcius Kelvin 212 100 373. 10.Water boils 32 0 273.15 Water freezes 459.67 273.15 0 ------- Absolute zero Physics 121: Lecture 24, Pg 5
Physics 121: Lecture 24, Pg 5 Temperature scales Three main scales 212 Farenheit 100 Celcius 32 0 273.15 373.15 Kelvin Water boils Water freezes -459.67 -273.15 0 Absolute Zero