Science December

Warm Up Bring your notebook, pencil, and agenda to your desk Grab a warm up from the front table Complete Monday’s warm up now YOU ARE QUIET, WORKING WHEN THE BELL RINGS

Let’s review what we learned on Fri before we get back to conductors & insulators. What is expansion? (Turn and talk with neighbors) 30 seconds What is contraction? (T & T) 30 sec What was an example of expansion that you saw in the Eureka video? What was an example of contraction that you saw in the Eureka video?

Expansion/Contraction Real World Examples

What does real world mean? Let’s discuss

Real World Examples Worksheet You will use this worksheet and your chromebook to go through today’s powerpoint This worksheet will be collected at the end of class

The following slides show real world examples Copy examples onto worksheet Example 1 Metal framed windows need rubber spacers Why? Think about what happens to windows in summer? In winter?

Real world Example 2 The video shows the right design for pipes in a home. They are made with expansion and contraction in mind. Pipes should not be used in long straight lengths fixed tightly to the wall. What would happen if they were fixed tightly to the wall in straight lengths? Play video. Stop at 1:20

Real world Example 3 A power line on a hot day is droopy, but on a cold day it is tight. This is because the metals expand under heat.

Real World -Example 4 Expansion and Contraction Joints below your notes… Bridge with expansion joints Sidewalk with expansion joints Road with no expansion joints….cracks over time with heating and cooling

Real World- Example 5a Large structures such as railways and bridges need expansion joints in the structures to avoid sun kink.expansion jointssun kink qvCqY2Hg qvCqY2Hg

Example 5b Real world: Kansas City News Report Train Track Accident Report

Real World Example 5c: solution to expanding tracks “Summer on the Railway”

Why is it important to consider expansion and contraction in the real world? Answer this question in your notebook Label the page December Real World Examples

Brain Twizzler Situation: It is a hot summer day. Janelle comes home and tries to shut her bedroom door but it won’t close. It keeps getting stuck! Task: What has happened to cause the door to stick and NOT shut. On the page labeled December Real World Examples, draw a before and after model of Janelle’s door.

Posters! You will create a poster on the back of your worksheet to represent: Thermal Conductors Thermal Insulators Electrical Conductors Electrical Insulators

Review of these concepts The remaining slides can be used to help you create your poster Remember all 4 terms must be included in your poster Art supplies (crayons and colored pencils are along the back counter) Remember this worksheet will be collected at the end of class today!

Thermal Conductors Includes metals (aluminum, steel, and copper) They transfer heat and they hold heat easily too.

Think about cookware…. Most cookware is made from different types of metals because they are thermal conductors

Examples of Thermal Conductors…

Thermal insulators do not conduct heat: plastic pot handles, spatulas, coolers, clothing, and home insulation They reduce (limit) heat transfer. They do not get hot as easily

Now let’s talk about Electrical insulators and Conductors

An electrical conductor is a material through which an electrical current can flow easily. Electrical energy can pass through conductors. Includes most metals

Examples of Electrical Conductors….

An electrical insulator is a material through which electrical current does not easily flow. Includes rubber, glass, porcelain, ceramic, plastics

Examples of Electrical Insulators….