1. Solid Gas Liquid INTERNAL ENERGY, U
Every object of matter, whether solid, liquid, or gas, consists of atoms or molecules in rapid motion. The kinetic energies of these particles constitute the internal energy of the body of matter.
Solid
Gas
Liquid

2. Heat Q, may be thought of as internal energy in transit
Heat Q, may be thought of as internal energy in transit. When heat is added to a body, its internal energy increases and its temperature rises; when heat is removed from a body, its internal energy decreases and its temperature falls.

3. A thermometer is a device for measuring temperature.
Temperature is familiar as the property of a body of matter responsible for sensations of hot or cold to the touch.
Temperature indicates the direction of internal energy flow: When two objects are in contact, internal energy goes from the one at higher temperature to the one at lower temperature.
The temperature of the body is a measure of the average kinetic energy of its particles.
A thermometer is a device for measuring temperature.

4. Temperature and Thermometers
Thermometers make use of physical properties that change with temperature.
Many physical properties can be used:
volume of a liquid
length of a solid
pressure of a gas held at constant volume
volume of a gas held at constant pressure
electric resistance of a conductor
color of a very hot object
Thermometers work by quickly getting to the same temperature as its surroundings
Temperature is a measure of how hot or cold something is.

5. Temperature Scales
Kelvin
Celsius
Fahrenheit
Boiling
Point (H2O)
373
100
212
Melting
Point (H2O)
273 32
Absolute Zero
-273
-459

7. Consider the way pressure changes with temperature in a gas:
Gay-Lussac’s Law P α T
Pressure
Temperature
Gas 1
Gas 2
Pressure must always be greater than zero
So temperature can never go below this point:
T = ° C = Absolute Zero

8. Determine Absolute Zero using Vernier Pressure sensor
Temperature and pressure demo.pptx –U-tube manometer

9. Pressure Law
Use Vernier and extrapolate temperature until P = 0 ie T should = -273C

10. A new temperature
unit: Kelvins (K)
0 K = absolute zero = ° C
Kelvins are the same size as Celsius degrees
Kelvins are the SI unit for temperature
To convert:
TC = Celsius temp.
T = Kelvin temp.
T = TC

11. Thermal Expansion
When the washer
is heated
The hole
becomes
larger

12. Some consequences of Linear Expansion:
Concrete buildings expand
Bridges need expansion joints
Dental fillings must expand at the same rate as teeth

13. Recall: Most materials expand if heated
Exception: Water contracts from 0°C °C
This is the most dense water gets (in any state)
Consequence:
In the winter, lakes freeze from the top down

14. Which is most likely liquid water?
discussion how do you know? A I am not sure that my students remember that water is less dense in solid form, but this would be a good time to remind them that ice floats.
A B C

15. Thermal Expansion DL Lo DL  LoDT DT DL = aLoDT L - Lo = aLoDT
Coefficient of
linear expansion
L = Lo(1+aDT)

16. Thermal Expansion Expansion Problem sleeve shaft D d
A cylindrical brass sleeve is to be shrunk-fitted over a brass shaft whose diameter is cm at 0 oC. The diameter of the sleeve is cm at 0 oC.
To what temperature must the sleeve be heated before it will slip over the shaft?

17. Thermal Expansion shaft sleeve Expansion ProblemD d
Expansion Problem
To what temperature must the sleeve be heated before it will slip over the shaft?

18. Thermal Expansion Volume Expansion New Volume Lo Lo + DL
Initial Volume
DL = aLoDT

19. Thermal Expansion
Coefficient of
Volume
Expansion

20. Thermal Expansion Expansion Problem
An automobile fuel tank is filled to the brim with 45 L of gasoline at 10 oC. Immediately afterward, the vehicle is parked in the Sun, where the temperature is 35 oC. How much gasoline overflows from the tank as a result of expansion?
Change in
volume
of the steel
gas tank
Overflow
Change in
volume
of the
gasoline