ETV – The Science of Colour of Light Light, Colours & Beyond

1. Newton made a triangular glass prism to study colours in year ________

2.White light passes through a triangular prism, it breaks down into light rays of different colours, from right to left, the first light colour appears is green violet red blue

3. Dispersion breaks down white light into light rays of different colours. There is no distinct borders between colours, with one colour gradually merging into another, scientists called this band of colour the rainbow. the spectrum. the dispersion. the electromagnetic spectrum.

4. Triangular prism causes dispersion of white light to give a range of colours. Why? Light rays of different colours have the same speed in air. After entering into glass, light rays of different colours experience different degree of refraction. Prism filters the white light. Prism adds colours to white light.

5. Triangular prism causes dispersion of white light to give a range of colours. Which colour light is most refracted? White light Red light Violet light Green light

6. Which of the followings are criteria of seeing a rainbow? (I) & (II) only (I), (II) & (III) (I), (III) & (IV) (I), (II), (III) & (IV) (I)When the sun comes out after a shower. (II)Turn a little away from the sun. (III)Facing the sky. (IV)Facing the sun.

7. Which of the following causes refraction of white light in the air and forms a rainbow? Water vapour Oxygen in the air Dust in the air Water droplets in the atmosphere

8. State how many times will white light refract and reflect in the water droplet to form the rainbow. Refracted once. Refracted twice. Reflected once and refracted twice. Reflected and refracted once respectively.

9. Red, blue and green light can combine to form the colour black colours of yellow, cyan and magenta light of any colours white light only

10. Appearance of colours on a TV screen is due to ________. refraction mixing of colour lights Subtraction of colour lights dispersion

11. The sense of colours is produced when _______ in the eye ball are activated. Cornea cells Rod cells Nerve cells Cone cells

12. Which of the following correctly states the approximate number of rod cells and cone cells on the retina? Six hundred million of rods and ten million of cones. one hundred and twenty million of cones and six to seven millions of rods. one hundred and twenty million of rods and six to seven millions of cones. Six hundred million of cones and ten million of rods.

13. Objects will appear to be _____ in a person with total colour blindness. Black and white coloured Grey in colour Multi-coloured Red in colour

14. The colour of an object refers to the colours of light it reflects the colours of light it absorbs the colours it possesses the paints on its surface

15. When red paint mixes with green paint, _______ colour will appear. yellow blue dull dark purple white

16. Sodium vapour lamp mainly gives out red light yellow light white light green light

17. A blue car appears to be _________ in colour under the illumination of sodium vapour lamp in the dark. yellow grey red blue

18. Which of the following colour light is scattered by particles in the air when the sun is directly overhead? red green blue yellow