Microwaves & Infrared

This lesson covers:

  1. The two main uses of microwaves
  2. The main uses of infrared radiation

shorter / longer


Microwaves and infrared waves have wavelengths than visible light.

longer

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Some frequencies of microwaves can be absorbed by water molecules.


Other frequencies of microwaves cannot be absorbed by water molecules.

Illustration of a microwave, satellite, and infrared camera.

Microwaves that can be absorbed by water molecules are used for:

Satellite communication

Seeing animals in the dark

Microwave ovens

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Microwaves that cannot be absorbed by water molecules are used for:

Seeing animals in the dark

Satellite communication

Microwave ovens

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some / all / heat


Infrared radiation is emitted from objects that have thermal energy.

all
heat

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Illustration of burning objects showing flames and barrels.

True or false? Higher temperature objects emit less infrared radiation than lower temperature objects.

True

False

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Infrared cameras specialise in spotting live organisms because:

(Select all that apply)

Animals are attracted to infrared camera

Animals are warmer than the surrounding environment and therefore emit more infrared radiation

Infrared cameras can detect the infrared radiation emitted by animals

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Infrared r can be used to cook food and heat a room.


Both rely on h metal to a very high t.


The hot metal e a lot of infrared radiation.

adiation
eating
emperature
mits

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