mr. z’s introduction to heat unit describe how heat is transferred through solids. distinguish...

Mr. Z’s

Introduction to HEAT unit

Describe how heat is transferred through solids.

Distinguish between the terms “insulator” and “conductor”

AIM: What is Conduction?


Conductor, Conduction, Conductor, Conduction, Insulator, ConductorInsulator, Conductor

What are the girls doing in this picture?

What do you think will happen to the wax?

Point #3 Point #3 Point #1

This is an all metal pot on a hot stove.

Do you think the handle will be hot?

Why?

Bunsen Burner, and a metal bar place near the flame.

The bar is made of million and million of what?

What happens to the bar as it is placed in the flame?

Molecules.

It gets hot!

When heat is added to a molecule, what does it do?

It begins to vibrate faster because of the added kinetic energy!

This heat travels from one molecule to the next!

The kinetic energy is LITERALLY passed from one molecule to the next until the entire “bar” is hot!

This is the process of CONDUCTION!

Heat Flow

Area of Highest Heat

Area of Lowest Heat

The bar literally gets hot one molecule after the next. Each time the molecule closest to the heat source passes the heat energy to the molecule next to it which has less heat. That is the way heat moves! Heat moves from an area of higher concentration (or heat) to an area of lesser heat!

AIM: What is Radiation

What did the Girl say “Ouch”?

Why did the wax at Point 3 heat up last?

Point #3 Point #3 Point #1

Why does the handle get hot?

Why do you think the grate gets hot in the fireplace?

AIM: What is radiation?

...the passage of energy (particularly heat or electricity)

through something.



PROBLEM: We add a metal spoon and a wooden spoon into a pot of boiling water.

Which one get hotter?

The metal of the spoon is a better conductor of heat then

wood.


DEMO PROBLEM #1:

•We add boiling hot water (for tea) into two cups.

•One is made of Styrofoam, and the other is made of glass.

•Which cup feels hotter?


PROBLEM #2: We add boiling hot water (for tea) into two

cups. One is made of Styrofoam, and the other is

made of glass. Which one get hotter?

Styrofoam is a better insulator of heat then glass. Glass is better conductor of heat!


DEMO PROBLEM #2:

•We add boiling hot water (for tea) into two cups.

•One is made of Styrofoam, and the other is made of glass.

•We can record the temperature every 5 minutes

•Which cup retain more of the heat?

Styrofoam is a better insulator of heat then glass. Glass is better

conductor of heat!


Conductors vs. Insulators

•Conductors transfer heat well.

•All metals are good conductors of heat

•Insulators do not transfer heat well.

•Name some good conductors?

•Name some good insulators.


Conductors vs. InsulatorsConductors vs. Insulators

•Why do we use an oven mitt?

•Why do we use wooden spoons?

•Why do we get hot coffee in special cups?

•Why are ice tray usually made of metal?

•Which way does the heat flow in an ice tray?

Why are these pots made out of the material that they are made out of?

Why do you think we add insulation to our homes?

Class Activity:

W/S 6-6


Homework:

INTERNET QUESTIONS
