Natural science heat and light

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Transcript of Natural science heat and light

Heat and Light.

Heat is the amount

of thermal energy an

object has.

is a form of energythat travels throughair and space in waves.

Thermal energy always travels from a hotter

object to a colder one. In 3 different forms.

Radiation

Conduction Convection

Thermal energy always travels from a hotter

object to a colder one. In 3 different forms.

Radiation

Thermal energy can be

transferred by space

through electromagnetic

waves.

Conduction.

Occurs when 2

objects are in

contact and

thermal energy

transferred from

an object to the

other .

Convection.

Occurs when thermal

energy travel trough

a gas or a liquid

Thermal energy always travels from a hotter

object to a colder one. In 3 different forms.

Radiation

Conduction.

Convection.

CONDUCTORS AND INSULATORS.

INSULATORSCONDUCTORS.

SOME

MATERIALS ARE

GOOD

CONDUCTORS

LIKE METAL.

A PAN

OTHER DONT

TRANSFER

ENERGY

EASILY.WOOD

CONDUCTORS AND INSULATORS.

INSULATORSCONDUCTORS.

THERMAL ENERGY CAUSES CHANGES IN THE

STATE OF SOME MATERIALS.

MELTINGEVAPORATION

EXPANSION

CHEMICAL

CHANGES

THERMAL ENERGY CAUSES CHANGES IN THE

STATE OF SOME MATERIALS.

MELTING.

WHEN A SOLID

TURNS INTO A

LIQUID.

MOLECULES

MOVE FASTER

EVAPORATION.

THERMAL

ENERGY MAKES

A LIQUID

CHANGE INTO A

GAS

THERMAL ENERGY CAUSES CHANGES IN THE

STATE OF SOME MATERIALS.

THERMAL ENERGY CAUSES CHANGES IN THE

STATE OF SOME MATERIALS.

EXPANSION.THERMAL ENERGY

CAUSES THE

MOLECULES IN A

SOLID, LIQUID OR

GAS TO VIBRATE, AS A

RESULT THE

MATERIAL EXPANDS.

CHEMICAL

CHANGES.Thermal energy can

cause chemical

changes like when we

make fairy cakes or

an omelette.

EXPANSION. CHEMICAL

CHANGES.

Light is a radiation that we can see with oureyes. It´s made up of microscopic particlesthat travel in waves.

Objects reactions to light

TransparentIt doesn´t

block light.

OpaqueIt blocks the

light

completely.

TranslucientSome objects

can block

light, but

some can pass

trough the

material.

Objects reactions to light

REFLECTION

REFRACTION

OCCURS WHEN LIGHT

ENERGY BOUNCES OFF A

SURFACE AND CHANGES

DIRECTION

OCCURS WHEN LIGHT PASSES

TROUGH SOME

TRANSPARENT SUBSTANCES

LIKE WATER, AND LIGHT

ENERGY CHANGES

DIRECTION SLIGHTLY.

REFLECTION REFRACTION

WHITE LIGHT

WHITE LIGHT IS MADE

UP OF ALL THE

COLOURS COMBINED

TOGETHER.

WE CAN DIVIDE IT BY

REFRACTION

WHITE LIGHT

When light energy hits an object,

some of this energy is absorbed by

the object.

This energy makes the molecules of

the object vibrate faster . If we touch

the object, we feel this vibration as

heat.