Thermal Energy Transfer

Thermal Energy Transfer

GRADE 10

Vocabulary

• conduction – the transfer of thermal energy when particles collide in matter

•  conductor – a substance through which thermal energy moves easily

•  convection – the transfer of thermal energy from hot to cold places by air or liquid

•  radiation – a form of energy transfer that occurs by electromagnetic waves

• insulator – a substance through which heat flows very slowly

• conductor - a substance through which heat flows fast

Conduction, Convection, Radiation

GRADE 10

​Heat and Heat Transfer

​Heat (or thermal) energy is the result of particle movement and generates heat.

​

Heat transfer occurs ​when heat energy transfer from one particle to another.

​

At a particle level, as particles heat up they start to move faster, they collide with each other, and the space between them increases. ​

​3 Types of Heat Transfer

​Conduction

• ​when particles are touching each other

Convection

• ​only occurs in fluids (liquids and gases)

• circular movement

Radiation

• ​heat travelling in waves through air or a vacuum

​THERMAL CONDUCTION

​Particles are closely packed together

​-particles at the end of the rod when heated will gain energy and vibrate the more energy the more vibrations.

​- they vibrate and touch neighbouring particle and heat energy is transferred.

​Convection

​Convection is a form of heat transfer, that only works in fluids (liquids or gases).

​

Heat source heats the bottom of the fluid, as it heats up the particles move further apart and become less dense, then the cooler water is more dense and falls to the bottom. Where it is then heated and will rise.

​

'Hot air rises'

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Examples:

• cooling a room with air conditioner

• boiling a pot of water​

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​Convection

​- is the way in which heat is transferred through fluids (liquids and gases) by movement of particles themselves

​

​- when particles are heated they expand and get less dense and rise; the cooler the particles get they contact become more dense and sink.

​

​- the constant circulation of hot (warm) particles moving upwards and the cooler particles moving downwards is called CONVECTION Currents.

​Convection Currents :sea and land breeze

​Radiation

Radiation is a form of heat transfer that does not need particles to travel through. Heat travels in waves, and can move through air and space.

​

Examples:

• he​at from a fire

• heat from the sun heating up outside of house

Multiple Choice

How does heat move?

• In many directions

• from warm places to cooler places

• from cold places to warm places

• Both B and C

Multiple Choice

What happens to particles as they heat up?

• They slow down

• Nothing

• They don't move

• They speed up

Multiple Choice

Cold Pack on Person

• Heat is transferred from the cold pack to the person.

• Heat is transferred from the person to the cold pack

• The cold pack is getting colder. The person is getting warmer.

Multiple Choice

If you burn your hand on the handle of a hot pot, heat was transferred to your skin by

• conduction

• convection

• radiation

• equilibrium

Multiple Choice

Which example below is an example of radiation?

• Standing on a hot metal bridge

• The attic is warmer than the basement

• The Sun heating the Earth

• Touching hot sand with your feet

Multiple Choice

What type of thermal energy transfer is number 2 pointing to?

• Convection

• Conduction

• Radiation

• Insulation

Multiple Choice

What type of thermal energy transfer is number 1 pointing to?

• Convection

• Conduction

• Radiation

• Insulation

Multiple Choice

Which example below is an example of convection?

• Standing on a hot metal bridge

• The attic is warmer than the basement

• The Sun heating the Earth

• Touching hot sand with your feet

Multiple Choice

What type of heat transfer takes place in solids?

• Conduction

• Convection

• Radiation

Multiple Choice

What type of heat transfer takes place in liquids and gasses?

• Conduction

• Convection

• Radiation

• Thermal Equilibrium

Multiple Choice

In what direction do hot liquids and gasses move?

• Side to Side

• Down

• Up

• Back and Forth

Multiple Choice

Radiation is a method of thermal energy transfer that moves -

• through empty space.

• when objects touch.

• only through solids.

• in the motion of fluids.

Multiple Choice

The heat from a hot burner to a pot is transferred by ______.

• convection

• insulation

• radiation

• conduction

Multiple Choice

Which of these methods of heat transfer does not involve particles?

• Conduction 

• Convection 

• Radiation 

Multiple Choice

Andy stirred a hot drink in a styrofoam cup with a  metal spoon.  In what order did the thermal energy reach Andy's hand?

• cup-hot chocolate-hand

• hand-spoon-hot chocolate

• hot chocolate-spoon-hand

• hot chocolate-spoon-hand-cup

Multiple Choice

In the winter, some people heat their homes by burning logs in the fireplace.  How does the heat from the fire get to the other side of the room?

• it travels through the carpet by conduction

• it travels through the air by convection

• it travels through the carpet by radiation

• it travels with the smoke by condensation

Multiple Choice

Warm air rises and the cool air sinks demonstrates this type of heat transfer. 

• conduction

• convection

• radiation

• Insolation 

Multiple Choice

The thermal energy transfer being shown in this image is...

• conduction

• convection

• radiation

Multiple Choice

What method of heat transfer can occur in a vacuum?

• Conduction

• Convection

• Radiation

Multiple Choice

The thermal energy transfer being shown in this image is...

• conduction

• convection

• radiation

Multiple Choice

To keep the baby chickens warm a farmer uses heat lamps, this is an example of ______.

• conduction

• convection

• radiation

• isolation

Multiple Choice

Conduction is heat transfer by -

• Touch

• Circles

• Waves

Multiple Choice

Which of the following are kinds of heat transfer.

• Conduction

• Convection

• Radiation

• All of the above

​Things to Note

​These will often combine - it is not as simple as it is made out to be.

​

For example:

A room is heated by radiation by a fire, but the entirety of the room is heated by convection, and specific objects within the room will be heated by conduction. ​

​

Heat transfer can be impaired by an insulator. This is a material that does not conduct heat well, for example, ​rubber, glass, or wood.

​

Multiple Choice

• Conductor 

• Insulator 

Multiple Choice

• Conductor 

• Insulator

Multiple Choice

• Conductor

• Insulator 

Multiple Choice

• Conductor

• Insulator 

Multiple Choice

• Conductor

• Insulator 

Multiple Choice

• Conductor

• Insulator 

Multiple Choice

• Conductor

• Insulator

Fill in the Blanks

Fill in the Blanks

Multiple Choice

Jenny poured some hot chocolate into a cup and stirred it with a metal spoon.  She noticed the spoon was really warm.  What is the best explanation for this?

• The spoon is a conductor.

• The spoon reflects heat.

• The spoon is an insulator.

• She touched the spoon first and waited to touch the cup.

Multiple Choice

A material that reduces the flow of heat is a(n)

• conductor

• insulator

• metal

• radiator

Multiple Choice

This is an example of a(n)

• Conductor of heat

• Insulator of heat

• Insulator of electrical

• None of the above

Multiple Choice

What type of material makes the best insulators?

• Aluminum

• Copper

• Styrofoam

• Metal

Multiple Choice

A material that reduces the flow of heat is a(n)

• conductor

• insulator

• metal

• radiator