Visible Light Flashcards
What happens to white light through a prism
It splits into a spectrum
How do coloured filters work
Work by absorbing specific wavelengths and transmitting other wavelengths
- filters absorb all colours of visible light apart from red
Best surfaces to absorb and emit infrared radiation
Matt black surfaces
What does wavelength and intensity of object depend on
Temperature of the object
Describe a perfect black body
Absorbs all the radiation incident on it
No radiation is reflected or transmitted
Best possible emitter of radiation
What happens if object is cooler than its surroundings
Will absorb more radiation than it emits
= cause temp to increase
What happens if object is at a constant temp
Absorbs radiation at the same rate as it’s emitting radiation
How does earth gain or lose energy
Absorbing or emitting radiation
How radiation affects temp of the earth
- sun emits short wavelength radiation
- radiation travels to the earth
- some radiation is simply reflected
- remaining radiation can be absorbed by surface of the earth
= causes temp of earth to increase - earth emits infrared radiation back into space
Effects of global warming on atmosphere
More heat energy is trapped in atom sphere and less is radiated into space
Factor that can affect how much energy is radiated from earth
Cloud cover
- cloudy nights are warmer than clear nights
= because clouds can reflect infrared back to earth and prevent it being radiated into space
