Chapter 8- Heat Transfer And its Consequences

1. Heat travels fom a place of higher temperature to a place of lower temperature.

2. The 3 process of thermal energy transfer are:
- Conduction
- Convection
- Readiation

3. Conduction is the transfer of heat energy through a material from the hot to the cold regions without any visible movement or flow of the material.

4. Substanes which conduct heat rapidly are called heat condutors.

Changes Of State

Melting

Meaning > change from SOLID to LIQUID without a change in temperature

Boiling

Meaning > change of state from LIQUID to GAS without a change of temperature

Freezing

Meaning > change of state LIQUID to SOILD without a change in temperature.




Condensation

Meaning > change of state of state of GAS to LIQULD without a change in temperature

Look!

good website for Celsius and Fahrenheit

Temperature And Thermometers

What is Temperature?

• Temperature is a measure of hotness or coldness of an object
• The hotter an object is , the higher the temperature.

Celsius Scale

• Commonly used
• Measured in degrees celsius
• Two fixed point: Lower fixed point Ice point (0 celsius), Upper fixed piont: Steam point (100 celsius)

Ice Point : Temperature of pure melting ice

Steam poitn: temperature of steam above boiling water at standad atmospheric pressure

Fixed points are needed as Standard reference point so that other temperatures can be defined

SI unit of temperature is: Kelvin(K)

Convert celsius to kelvin (+273)

Convert kelvin to celsius (-273)

How does a Thermometer work?

• Thermometer uses a Phiysical Property that change steadily with temperature