This document discusses key concepts about temperature and heat transfer. It defines temperature as a measure of how fast particles are moving, with higher temperatures indicating faster particle motion. It explains that temperature is measured using thermometers and different scales like Fahrenheit, Celsius and Kelvin. The document also describes the three main methods of heat transfer as conduction (through direct contact), convection (circulation of fluids like gases and liquids), and radiation (transfer of electromagnetic waves). It identifies materials that conduct or insulate heat well and provides formulas for calculating heat transfer.

1. Temperature
• The measure of how hot or cold
something is
• Specifically – how fast the particles are
moving, average kinetic energy
• Matter is made of atoms that are always
moving, or they have kinetic energy
• The more kinetic energy, the higher the
temperature

2. • Measuring temperature measures the average
kinetic energy of an object
• Temperature is measured with a thermometer
• Thermal expansion – increase in the size of a
substance in response to an increase in temp
(as temp increases, particles move faster,
spreading out)
• Because of thermal expansion, all materials can
expand and shrink when temperature changes

3. • Mercury and alcohol are used in
thermometers because they increase in
size (expand) by constant amounts, stay
liquid at high and low temperatures
• Fahrenheit
– Boiling pt 212°
– Freezing pt 32°

4. • Celsius
– Boiling pt 100°
– Freezing pt 0°
• Kelvin
– Boiling pt 373
– Freezing pt 273
• Lowest temp on Kelvin scale is 0 or
absolute zero (-459°F), the temperature at
which all molecules stop moving

5. • Heat – the energy transferred between
objects that are at different temperatures
• Thermal energy – kinetic energy of a
substances atoms
• Thermal energy is transferred from areas
warmer to areas that are cooler until both
are equal

6. Conduction – the transfer of energy, as
heat, through a material (touching)

7. Conductors and Insulators
• Materials that transfer heat are called
thermal conductors
• Materials that do not transfer heat are
called thermal insulators
• Examples:
– Insulators: feathers, blankets, plastics
– Conductors: metals
• Thermal conductivity is the rate at which a
material conducts heat

8. Radiation – the transfer of energy
as electromagnetic waves (sun)

9. • Radiant energy from the sun heats earth
• Examples:
– Fire
– Radiator
– Electric Oven
– Electric stove

10. Convection is the transfer of thermal energy
by the circulation or movement of a liquid or
a gas

11. • Energy transfer can not be measured
directly, instead it must be calculated
• Heat = joules (J)
• Specific heat = (J/Kg x ° C)
• Mass = Kg
• Temperature = ° C
• Formula to calculate heat:
J = (J/Kg x ° C) x Kg x ° C

12. Review