2. What happens to white light when it passes through a filter? 3. Which colours can pass through a blue filter? 4. Which colours cannot pass through a blue filter? 5. Which colours can pass through a green filter? 6. Which colours cannot pass through a green filter? 7. Which colours can pass through a red filter? 8. Which colours cannot pass through a red filter? 9. Imagine that you put a green filter next to a blue filter, so that white light had to pass through one filter after the other. Would any light come through? Which colours will be able to pass through? 10. Which two filters, if placed together, would absorb all colours of light? 11. What do you mean by colour addition? 12. What are the primary colours? 13. What do you mean by colour subtraction? 14. Why do we see grass as green in colour? 15. Why do we see red post boxes as red in colour? 16. Which colour of lights are reflected by a black object when white light falls on it?
Answers
Explanation:
2.Colour filters
When white light passes through a coloured filter, all colours are absorbed except for the colour of the filter. For example, an orange filter transmits orange light but absorbs all the other colours.
3.So when blue light is allowed through a blue filter onto a blue object, the object will still reflect blue and therefore appear blue. But when blue light from a blue filter hits a red object, the blue will be absorbed and no light will be reflected, giving the object an appearance of being black.
4.A pure red filter only allows red light through and a pure blue filter only allows blue light through, so if these filters are used together no light can pass through at all.
5.Most light sources emit a broad range of wavelengths that cover the entire visible light spectrum. In many instances, however, it is desirable to produce light that has a restricted wavelength spectrum. This can be easily accomplished through the use of specialized filters that transmit some wavelengths and selectively absorb or reflect unwanted wavelengths.
6.