1. Summary of This Week’s Lab
Conductometer
Thermal Expansion
Convection

2. Conductometer View the Video -Order from best to worst conductors:
Copper
Aluminum
Brass*
Stainless Steel*
Nickel
* alloys

3. Thermal Expansion Ball and Ring Lab - View the Video
_____________– when molecules are heated
Molecules move further apart and take up more space
Objects get bigger
_____________ – when molecules cool down
Molecules move closer together and take up less space
Objects become smaller
PBS activity

4. Everyday Examples Bridges have “teeth” or expansion joints
Concrete sidewalks have spaces or grooves
Exception to the rule: between 32 and 39 water _________ and expands
Ice is less dense than water and floats

5. Convection Heat transfer caused by ____________ differences
Liquids and gases
Hot gases or liquids- ________because it’s less dense
Cold gases or liquids- ________ because it’s more dense

6. Convection
Look at the following site and copy down the picture of the heater- mark the heat flow with 2 different colored pens/pencils
View the animation

7. Overall summary Heat is transferred in 3 ways: _____________
It travels from ___________ to ____________ places
It is measured in calories.
Temperature change = Final Temperature – Initial Temperature
Heat = Volume X Temperature change

8. CONDUCTION Heat transfer by contact/collisions Happens in ______
Better in high density objects

9. Convection Hot air/water is ______ dense and will ______________.
Cold air/water is ______ dense
and will ___________.
This results in convection _____________.

10. Radiation Doesn’t require a medium (solid, liquid or gas)
Can happen through outer space or empty space (a vacuum)
Energy travels as light wave and some of it is then converted back to heat