8U3L5 Heat Transfer Introduction

Heat Transfer

 8.MS-PS1-4. Develop a model that describes and predicts changes in particle motion, relative spatial arrangement, temperature, and state of a pure substance when thermal energy is added or removed.

Open Ended

Heat transfers (moves) all the time around us! Describe an example of heat moving from one object to another that you have experienced:

Notebook Setup

• First Page - Table of Contents

• Second Page (Or next open page) - Heat Transfer Notes

• Last Page - U3L5 Heat Transfer Vocabulary

Write these vocabulary words and definitions in your Notebook

• Conduction - the transfer of heat energy from particle to particle between substances through contact or within a substance

• Conductor - a material that allows heat to easily transfer through it.

• Convection - the transfer of heat energy through the movement of gas or liquid currents

• Equilibrium - when all parts of the system are at the same temperature

• Heat - the energy that an object has because of the motion of its molecules

Write these vocabulary words and definitions in your Notebook

• Heat transfer - the movement of heat energy from a warmer substance to a cooler substance

• Insulator - a material that does not allow heat to transfer through it

• Radiation- the transfer of heat energy by electromagnetic waves that can travel through space

• Temperature - a measurement of the speed of vibration of the molecules of a substance

• Thermal energy - another word for heat

Heat Transfer Notes

Heat is a type of energy

• It is also known as THERMAL ENERGY

• Heat TRANSFERS or moves from one substance to another.

Multiple Choice

In this picture, heat is _________ from the radiator to people's hands.

• removing

• transferring

• energy

There are three types of heat transfer

• Conduction

• Convection

• Radiation

Conduction

• The movement of heat through matter

• The movement of heat from one object to another when they are IN CONTACT or TOUCHING.

• Solids are good conductors - metals are the best!

Convection

• The transfer of thermal energy through gas or liquids

• When gases or liquids get warm, the molecules move more and farther apart

• Because warm gas or liquid is now less dense, it will rise to the top, pushing cool gas or liquid down

Radiation

• Thermal energy that transfers with waves

• Radiation is the only type of heat transfer that can happen with no particles (and in space!)

• Radiation is often associated with light

Multiple Choice

What type of heat transfer is shown?

• Conduction

• Convection

• Radiation

Multiple Choice

What type of heat transfer is shown?

• Conduction

• Convection

• Radiation

Multiple Choice

What type of heat transfer is shown?

• Conduction

• Convection

• Radiation

When trying to figure out what type of heat transfer something is:

• Conduction - must be TOUCHING

• Convection - only gas or liquid

• Radiation - travels in waves through space

Examples of Conduction

Items must be in contact (touching)

Examples of Conduction

• Touching a metal spoon that is in a cup of hot liquid

• Putting a heating pad on your back

• Grabbing hot food

Examples of Convection

Only in gases or liquids

Examples of Convection

• Lava lamp wax rising when hot, falling when cooler

• Hot magma rising in the mantle and then sinking

• Hot air rising by the heater and circulating in the room

• Hot water rising in the ocean and sinking

Examples of Radiation

Heat traveling by waves

Examples of Radiation

• Cooking in a microwave oven

• Laying in the sun at the beach (notice it's so much colder in the shade)

• Feeling the heat from a bonfire

• Holding your hands over a light bulb

Let's Test Your Knowledge!

Multiple Choice

The baby chickens are kept warm from the heat lamps.

• conduction

• convection

• radiation

Multiple Choice

Warm air rises and the cool air sinks.

• conduction

• convection

• radiation

Multiple Choice

The man goes to take the hot pot off the stove with his bare hands.

• conduction

• convection

• radiation

Multiple Choice

Walking on the warm sand with your bare feet.

• conduction

• convection

• radiation

Multiple Choice

A group of friends gather around a fire to stay warm.

• conduction

• convection

• radiation

Multiple Choice

When you heat a pot on a stove, the handle gets warm. Which type of heat transfer is responsible?

• Conduction

• Radiation

• Convection

Multiple Choice

The sun shines down on this family as they play on the beach.

• conduction

• convection

• radiation

Multiple Choice

All of the following are examples of convection currents, except:

• Warm air rising in a house

• Cold water sinking to the bottom of the lake

• Water flowing through pipes

• Steam from hot soup rising into the air

Multiple Choice

Last one! Convection currents occur:

• Only in liquids

• When a dense substance is warmer than a less dense substance

• In both liquids and gases

• Weakly in solids