Constituent colours of white light from the sun.pptx

Class 7 Science Light

1. Constituent colours of white light from the sun Dispersion

2. V I B G Y O R

3. How is a rainbow formed?

4. Newton’s Disc Newton's colour disc has colours of the rainbow When the colour disc is rotated all the colours fade to white.

5. Examples

6. Primary colours These are the c olours of light by mixing which white light is obtained It is impossible to obtain either red, or green, or blue light by mixing the light of any two other colours Red + Green + Blue = White

7. Secondary colours These are the colours of light which are obtained by mixing two primary colours together

8. Red + Green = Yellow

9. Green + Blue = Cyan

10. Blue + Red = Magenta

11. Primary Colours Secondary Colours Blue Yellow ( Red + Green ) Green Cyan ( Green + Blue ) Red Magenta ( Blue + Red )

12. Yellow + Blue = White Magenta + Green = White Cyan + Red = White

13. Why do we use indigo while washing white cloths?

14. Applications Colour Displays Stage Lighting Colour Mixing in Art