Agenda Bell WorkNotes: Intro to Thermal • What is the Energy difference between a hot cup of coffee and a cold cup ofTemperature Scale coffee? Reseach - List everything youHW: Chp 9 pg 135- can think of. 136, 138-139, 144- 147
• What is the difference between a hot cup of coffee and a cold cup of coffee?- List everything you can think of.
Objectives1. Explain the motion of molecules in the different states of matter2. Understand the definition of thermal energy3. Describe what happens in thermal equilibrium
Movement of atoms• All matter is constantly moving• Moving particles determines whether an object is solid, liquid, or gas
Kinetic Energy• The warmer an object is the more kinetic energy it has = more thermal energy
Thermal Energy• The total energy of all it’s atoms and molecules
Hot or Cold• Temperature• Thermometer measures temperature by expansion or contraction of a liquidEureka 20
Temperature• Related to the random motion of atoms and molecules• average kinetic energy of molecules
• Thermometers read their own temperature• Energy flows between the thermometer and the object until they reach an equal temperature• This equilibrium is called a Thermal equilibrium
• Who created the temperature scale? • When was it created?• Celsius • How or why did they create it?• Fahrenheit • What is the temp of: (put them in• Kelvin order) – Liquid nitrogen – Body temp – Boiling water – Freezing water – Room temp – Absolute zero • What is the conversion to the other two scales?
Flow of Thermal Energy• From a warmer substance to a colder one• HEAT – thermal energy in motion
What’s cold?• The absence of thermal energy• An object is cold because of the loss in thermal energy• Eureka 21
Heat• Measured in Joules• 4.2 Joules of heat to change 1 gram of water 1 Celsius degree
c alorie• Unit of heat used in the United States• Amount of heat needed to change 1 gram of water 1 Celsius degree• 1 c alorie = 4.2 joules
• Energy ratings of food and fuels are measured by the energy released when they are burned• Kilo calories = C alories we know on food packages (capitol C)
• To the Weight Watcher, the peanut contains 10 C alories• To the physicist, it releases 10,000 c alories of energy when burned or digested