Study Hall: Welcome Back!

Sharpen your pencils….Find your seat……

Work on something quietly at your desk…

Warm Up – List 5 ways you…. • Used electrical energy over break.

• Used mechanical energy over break.

• You should have 10 total!

Volunteers to share with the Class?

• Electrical Energy:

• Mechanical Energy:

Announcement• There will be MAP testing tomorrow

during your 1st and 2nd block class.• Discovery Place (Any parents want to

come?)• Notebook check for those who did

not get a grade last Friday

Science Fair• Science Fair form signed today.• Hand your proposed science Fair Question to

me on Wednesday.• This is your homework.• Remember-

Is your question testable?Can you afford the materials?Are there variables included?

Our mission this week is to…

• To be an expert on conductors and insulators.

Interactive Notebook Q2

• Add entry to Table of Contents• 6.P.3.3 Insulators and Conductors• Assign the next number

Interactive Notebook Q2

• Label Next Available Page: • 6.P.3.3 Insulators and Conductors• Number page to match Table of

Contents entry• Circle the number

Write this in your notebook

• Electrical energy can also pass through conductors.

• An electrical conductor is a material through which an electrical current can flow easily.

• Includes most metals

Examples of Electrical Conductors….

Write this in your notebook….

• An electrical insulator is a material through which electrical current does not easily flow.

• Includes rubber, glass, porcelain, ceramic, plastics

Examples of Electrical Insulators….

Let’s test what’s an electrical conductor or insulator!• Copy chart in your notebook:

“Our Conduction & Insulator Experiment”• “Object Hypothesis

(Conductor/InsulatorResult

(Conductor/Insulator)

Write this in your notebook….

• Thermal energy is transferred through a material by the collisions of atoms within the material.

Remember Thermal Energy? Think about the Atoms….

• Copy this into notebook• How do atoms move when they gain heat

energy (states of matter changes)? • They expand, spread & bump into one

another• This allows the heat to move!

Remember???

• Over time, thermal energy (heat) spreads out through materials because of the atoms:

–It can travel by conduction (2 or more materials in direct contact with one another)

• It can travel by convection (currents in air, water and other fluids)

• It can travel by radiation ( when heat is transferred over

space in electromagnetic waves)

Write this in your notebook….

• Thermal energy can warm objects Examples: the inside of a car sitting in the sun

with the windows closed, and a cup of boiling water.

• Materials will cool down over time if thermal energy is not striking it.

Examples of Thermal Energy

Write this in your notebook….

• Some materials we use easily conduct heat• Includes metals (aluminum, steel, and copper)• We call these materials thermal conductors

because they transfer heat and they hold heat easily too.

Thermal insulators

• http://www.youtube.com/watch?v=43xcvSSFFxc

Examples of Thermal Conductors…

Think about cookware….

• Most cookware is made from different types of metals because they are thermal conductors

Write this in your notebook….

• Some materials we use do not conduct heat• Includes pot handles, spatulas, cooking

utensils• We call these materials thermal insulators

because they reduce (limit) heat transfer • They do not get hot as easily

Think about cookware….

• Notice the handles on the cookware…..• The handles do not conduct heat because they

are thermal insulators

Write this in your notebook….

• Expansion joint strips in bridges allow for the bridge to expand in hot weather and not break.

• These same joint strips allow for the bridge to contract in cold weather and not break.

Examples of Expansion and Contraction Joints…

Bridge with expansion joints

Sidewalk with expansion joints

Road with no expansion joints….cracks over time with heating and cooling

Demonstration…

• Could we make a bubble get bigger using a metal soda can or a plastic soda bottle?

Demo Results….

• When we held the metal can, the heat was easily conducted (transferred) from our hands through the metal = metal is a thermal conductor!

• Our bubble grew larger!• When we held the plastic bottle, the heat was not

easily conducted (transferred) from our hands through the plastic = plastic is a thermal insulator!

• Our bubble did not grow larger!