DAY 105

Essential Question: How does thermal energy flow?

announcements: quiz next tue/wed

review today and next class

Goals

1. State whether wood or iron or air are good conductors or good insulators

2. Define Radiation, Conduction, and Convection

3. Label the direction of heat flow

Warm-Up 105

1. What characteristic of air makes it a poor conductor?

2. For objects to conduct electricity, they must (be in contact/not be in contact/be friends)

3. For objects to conduct thermal energy, they must ______

4. Compare three things which are in your house and at room temperature (aka, not being warmed by you or the sun). Touch something metal (Like a chair leg), something wood (like a dresser or table), and something cotton (like a shirt in your closet). Which feels the coldest?

CLASSWORK

1. Conduction Review from 104C

1. Prof Hewitt says you can touch _______ when it's hot out of the oven. Is that true?

2. Would you want to touch hot wood for a short or long period of time? Why?

3. Which would be safer for you to touch, 100*C (212*F) wood, or 100*C (212*F) iron. Why? Starts with C, ends with....

4. Why is air a poor conductor? Think about the particles in are. Are they closely packed together (high density) or spread out (low density)

5. How do the down comforter, animal fur, styrofoam, or thermal underwear keep you warm?

6. How does holding air prevent energy transfer?

2. 105A: Guided Exploration - Heat Transfer

Link: https://docs.google.com/document/d/1bHVHDrvpxXWuVV5aPJqGyTZA_aLteRop9K-hdcjwA1o/edit?usp=sharing

3. 105B. Venn Diagram

In your notes, make a Venn Diagram for the three types of Heat Transfer. Don't forget to make the middle of the diagram (and the parts where two things are shared) big enough

List at least 7 things in your diagram

Upload a pic of your diagram to the Schoology assignment

In the chat, say what you put in the middle

*2021 add the 10 or 50q quiz review

4. Exit question:

Of the three energy types, which was/is the type used in transferring all the energy we've ever had?

Learning at Home/HW

- Complete any remaining CW from today

- Thermodynamics Quiz coming soon Thursday on Days 101-107

Goals

1. Model how a system of a hot object and a cold object will change over time

2. Convert temperatures between ºC and ºK

3. State whether wood or iron are good conductors or good insulators

Warm-Up 105

1. What is the relationship between energy and temperature?

2. Two objects with different temperatures are placed in contact. When will energy stop flowing from high (hot) to low (____)?

3. What is 20ºC in Kelvin?

CLASSWORK

1. 104B continued: Temperature & Energy Activity

1. Complete #7

2. Use the following link if you'd like to test out an idea before putting it to paper https://phet.colorado.edu/sims/html/energy-forms-and-changes/latest/energy-forms-and-changes_en.html

2. 105A: Conversion Practice

Copy, and complete

1. As thermal motion of atoms increases, temperature ___________.

2. As the temperature of an object drops, the thermal motion of atoms, and thus their kinetic energy ______________.

3. Fill in the temperature for Absolute Zero for each scale: _____ºC _______ºK

4. Copy & complete the following chart. Wondering where ºF is? We'll do those conversions another day :)

LINK: https://drive.google.com/file/d/1mAnUsb7bCzzWlAnjK5sAWqu9vz2HlJdO/view?usp=sharing

105C: Conduction Introduction

Copy and Answer the following while watching the video