1. Holt Physics, Chapter 10
Heat

3. Defining Temperature Feeling hot or cold
Need a more precise definition for how “hot” or “cold” something is.

4. Adding or removing energy usually changes the temperature of an object.
Temperature is proportional to the average KE of the atoms or molecules

7. Temperature is meaningful only when it is stable
Internal energy – energy of a substance due to the random motion of its component particles.
Equals to the total energy of those particles.
Symbol for internal energy: U
Temperature is meaningful only when it is stable
Warm fruit juice, cold beaker of water
Thermal equilibrium – state in which two bodies in contact with each other have identical temperatures.
It’s how a thermometer works!

8. Matter expands as its temperature increases.
Called thermal expansion
Coefficient of thermal expansion
Peculiarity of water
The expansion of liquids can be used to measure temperature.

9. Measuring Temperature
Make use of a physical change that corresponds to a change in temperature.
Volume of a gas or liquids
Pressure of a gas at a fixed volume
Most common thermometers
Mercury, colored alcohol, or mineral spirits

11. Calibrating a thermometer requires fixed temperatures.
Ice point: 0 oC
Steam point: 100 oC
Temperature units depend on the scale used.
Most widely used today are the Fahrenheit, Celsius, and Kelvin (or absolute) scales.
Celsius and Fahrenheit: differ in ice point and degree size
Celsius and Kelvin: differ in ice point only, degree size same
Celsius and Fahrenheit can be positive, negative, and zero values