absorbing and emitting radiation

What do all objects do

Absorb an emit radiation

Analyse graph - what does it show

Very hot objects emit shorter wavelength radiation than cooler objects

What happens if an object absorbs radiation and emits radiation

If object absorbs it will get hotter (radiation is pure energy)

If it emits it will cool down

What does the balance between absorbing an emitting radiation effect

The objects temperature

What happens to an object that is hotter than its surroundings

More radiation will be emitted than absorbed so overall it will lose energy and cool down

What happens to an object that is cooler than its surroundings

Less energy will be emitted than absorbed so it will slowly warm up

What happens if an object absorbs and emits the same amount of energy

It will stay the same temperature because it’s gaining and losing the same amount of heat

What does intensity mean, in terms of infrared radiation?

The power of the radiation per unit area - it’s a measure of how much energy the radiation transfers to a given area in a certain amount of time

The higher the intensity the higher the wavelength being emitted

What happens to the wavelength as the temperature of an object increases

The intensity of every emitted wavelength increases

But the intensity of the shorter wavelengths increase more than longer

During the day what happens to the earth (in idea of absorbing emitting )

During the day more energy is being absorbed by the earth and atmosphere than it’s being emitted which increases the local temperature

At night what happens to earth (in terms of absorbing and emitting)

At night less energy is absorbed than emitted an so local temperature decreases

Note

Overall some part of the earth is always in the sun so the overall temp stays constant