1. Chapter 10 Heat and Temperature

2. I. Temperature
A measure of the average kinetic energy of all the particles within an object.
The faster the particles move, the higher the temperature
Thermometers
Liquid in column expand and rise as the temp increases.
Can only measure temps between freezing/boiling points of liquid in thermometer.

3. II. Temperature Scales Fahrenheit- only used in U.S. ( ̊ F)
Celsius- based on the freezing point of water ( ̊ C)
Kelvin- mainly used in science (K)
O K is absolute zero: the point at which motion of particles in a substance stops
Not “degrees kelvin”- just kelvins

4. III. Temperature Conversions
Celsius—Fahrenheit: TF = (1.8 x TC ) + 32
Fahrenheit—Celsius: TC = (TF – 32) / 1.8
Celsius—Kelvin: TK = TC
Kelvin—Celsius: TC = TK

5. A little comparison…
Temp. Scale
Water Freezes
Room Temp
Body Temp
Water Boils
Fahrenheit
Celsius
Kelvin 32 70
98.6
212 37 21
100
273
294
310
373

6. Example
The highest atmospheric temperature ever recorded on Earth was ̊C. Express this temperature in both Fahrenheit and in Kelvins.
TF = (1.8 x 57.8) + 32
TF = 136 ̊ F
TK =
TK = 331 K

7. IV. Energy Transfer
Heat- the transfer of energy between objects with different temperatures.
Methods
Conduction-
occurs when two objects with different temperatures are in contact.
Rapidly vibrating atoms collide with slowly vibrating atoms
Convection-
Happens in liquids or gasses
Warmer substances expand and rise
Cooler substances replace the warmer ones
Radiation-
transfer of energy by electromagnetic waves

8. You feel the wire get hot by conduction.
Embers from the fire shoot up as warm air rises by convection
You feel warmth from the fire because of radiation

9. V. Insulators and Conductors
Conductors – materials that transfer heat easily
Solids are the best conductors- particles are close enough together to collide easily
Metals are generally the best solids for conduction
Gasses are the worst because the particles are spread too far apart

10. Insulators and conductors (cont)
Insulators- reduce the transfer of heat energy
Wood
Cotton
Fiberglass