Complement colours

[kenhung123]

Do you think we would need to know the complement colours e.g. what colour light is needed for a green solution

[KRISTOFFA]

Nah.

[stonecold]

Draw ROY G BIV in a circle, then the opposite colour is complementish....

And ROY G BIV = Red Orange Yellow Green Blue Indigo Violet

[scocliffe09]

Draw ROY G BIV in a circle, then the opposite colour is complementish....

And ROY G BIV = Red Orange Yellow Green Blue Indigo Violet

It is worth knowing - they can sometimes assume you know it for a multi choice, or they could ask a biology-ish question about photosynthesis or something (e.g. if I wanted to test for the amount of chlorophyll in a chloroplast what colour of light would I use? They'd obviously give you more info, but essentially, you work out that because the plants/ chlorophyll are green, you use red light)

[kenhung123]

Neat trick thanks

[stonecold]

On todays exam scoliffe the answer was unfortunately blue light for photosynthesis.  VCAA are so gay at times.  Most people picked red though, including me

[scocliffe09]

red and blue are both correct - chlorophyll absorbs at both. how do you know what VCAA picked?

[stonecold]

It was a multi choice question, and apparently blue is adsorbed slightly stronger

[kenhung123]

Far out I'm confused about colorimetry now. So how does it work again? I remember the solution colour that appears is the colour least absorbed, therefore the colour complement must be produced for analysis since most absorbed. But since the colour complement appears the colour the is most absorbed, doesn't it mean the same thing? It absorbed the colour most absorbed by solution therefore doesn't produce coloured desired?

[olly_s15]

Far out I'm confused about colorimetry now. So how does it work again? I remember the solution colour that appears is the colour least absorbed, therefore the colour complement must be produced for analysis since most absorbed. But since the colour complement appears the colour the is most absorbed, doesn't it mean the same thing? It absorbed the colour most absorbed by solution therefore doesn't produce coloured desired?

the colour seen is a result of the reflection of all colours except for the one seen

[kenhung123]

Isn't it the otherway around?

[olly_s15]

nooooooooooo it isn't

[kenhung123]

You see a particular colour because its reflected into our eyes..

[olly_s15]

You see a particular colour because its reflected into our eyes..

i disagree

you see a particular colour because every other colour except that colour is absorbed by the object