Blue sky and the preferential scattering of light
Blue sky and the preferential scattering of light in the atmosphere Why is the sky blue? Why are sunsets red?
Atmosphere You see light from the Sun that is aimed directly at you, but you won’t see light that is not travelling towards you. Right? Wrong!! What? ! Why? !
Sun Atmosphere Why is the sky blue? Every part of the sky (except the bit in the direction of the Sun) is sending predominantly blue light, so all these parts appear blue
Why is the setting Sun red? Atmosphere
Bad news alert: your brain does strange things with the colours your eyes actually see. Good news alert: everybody’s brains are similar, so it doesn’t really matter!! Question: Do we see colours as they truly are? Answer: No Our brains cope with these 7 different colours in different places. But what happens put these colours in the same place? Our brains make us believe that we see just one colour – white! White: the colour we think we see when the ‘right’ colours ‘arrive’ from the same place!! Black: the colour we think we see when our eyes see nothing!! So when you see black ink on white paper, you are actually seeing ink with no colour on multicoloured paper.
It’s also true that if white light is split, you see different colours… Glass prism Where the light would go if it wasn’t refracted Red refracts slightly ght i l te i Wh 7 colours in one place, therefore appears white Blue refracts more Violet refracts most but we don’t see much violet from sunlight 7 colours no longer in the same place so now appearing as 7 colours
- Slides: 6