Where does heat come from?

Touch each image and discuss.

Motion can produce heat. The amount of heat produced depends on the amount of motion.

How can motion create heat?

Touch each image to view the different energy levels of the molecule.

Water is made of molecules. Molecules are always in motion. The energy level of the molecules determines the state of matter.

What is heat?

Touch each image to see how the water molecules react.

Heat is a form of energy caused by the internal motion of molecules. The hotter a substance is, the faster the molecules are moving.

What is heat transfer?

Drag the hand over the ice or pan, observe the heat transfer for each.

Heat transfer is when heat energy moves from a warmer object to a cooler object.

heat transferred through empty space by invisible

infrared rays.

heat transferred through a liquid or gas by means

of up-and-down.

heat transferred by the direct contact of molecules.

What are the three type of heat transfer?

Conduction

Convection

Radiation

Conduction

Touch the image.

Conduction is the transfer of energy through matter by direct contact of particles.

Do some substances conduct heat more rapidly than others?

Write your answers and touch the clouds to reveal some examples.

Can you think of objects that are used to conduct heat or energy?

Copper wire conducts energy.

Metal pots and pans conduct heat to cook food.

Do some substances conduct heat and energy poorly?

Write your answers and touch the clouds to reveal some examples.

Can you think of objects that are used to stop the conduction of heat or energy?

A winter coat stops energy from being conducted out of a body.

A hot pad stops conduction from a hot pan to the hand.Insulators are substances that do not conduct heat and energy

well. Cloth, wood, glass, plastic, and rubber conduct energy and heat very slowly when in contact with vigorously moving particles of a hot object.

Conduction Lab

Drag the objects to connect the battery to the light bulb. Find out which items conduct energy.

Convection

Click on the red molecule to view the 4 stages of convection.

Convection is heat that is transferred in liquids or gases by means of up and down movements of matter.

Cycles are created called convection currents.

Draw the direction of the heat flow in the air above the land and the ocean.

During daytime, the temperature of the land is higher than the temperature of the ocean.

At night, the temperature of the land is lower than the temperature of the ocean.

Draw the direction of heat flow in the air above the land and the ocean.

Radiation

Touch each image to see examples of heat radiation.

Radiation is the heat energy that is transferred through empty space by invisible infrared radiation.

Review Question

Drag the correct answer to match definition.

1) Energy caused by motion of particles in matter.

2) Tiny particles that make up matter.

Heat Transfer

Molecules

Heat

Answer Options

HeatMoleculesHeat Transfer

3) Movement of heat from a warmer to a cooler object.

· · ·

Review Question

Drag the correct answer to match definition.

1) Movement of heat by direct contact.

2) Movement of heat that is transferred through empty space.

3) Movement of heat in an up and down motion of particles that occurs in liquids and gases.

Convection

Radiation

Conduction

Answer Options

RadiationConductionConvection· · ·

Review Question

Drag the correct answer to match the example.

3) Radiation2) Conduction1) Convection

1) Bacon cooking in a pan.

2) Air above a grassland plain warming up in the sun causing violent updrafts that lead to the formation of a tornado.

3) The warmth of a fireplace heating a person in a room.

Answer Options

Conduction Radiation Convection· · ·

1

A They are good conductors of heat.

B They are poor conductors of heat.

Why should the handle of a pot be made of wood or plastic rather than metal?

2 What happens to molecules as they heat up?

B They move less vigorously.

C They move more vigorously.

D No change occurs.

A They burn up and stop moving.

3 Which is moving faster- particles in a gas or a solid?

A gas

B solid

4 What happens to molecules as they cool down?

A They freeze and stop moving.

B They move less vigorously.

C They move more vigorously.

D No change occurs.

5 Cold air is denser than hot air?

A True

B False

6

A rise, heat up, sink, cool

B sink, cool, rise, heat up

C heat up, cool, rise, sink

D heat up, rise, cool down, sink

What is the correct order of a convection current?

7

A convection

B conduction

C radiation

In which type of heat transfer do particles actually move around?