1. Power of Sunglass is

2. Consider the following statements.
1. Fibre optics is based on the principle of total internal reflection.
2. In an optical fibre communication system, power consumption is extremely low.
3. Optical fibre communications are free from radio frequency interference.
4. In India, Reliance Group of Industries is engaged in the manufacture of the optical fibre. Which of these statements are correct?

3. The Sun appears red during Sunset

4. When a person enters into a dark room from the strong light area, he is not able to see clearly for some time. Later he gradually begins to see things. This is because

5. Optical fibre works on the principle of

6. For reproducing sound, a CD
(Compact Disc) audio player uses a

7. Reading glasses are made from which type of lenses?

8. For normal eyes what is the minimum distance for clear vision?

9. The number of colours contained in the Sunlight is

10. Which one of the following colours is seen in the middle of a Rainbow?

11. The formation of glittering colours in thin foam of soap is the result of which of the following phenomenon?

12. Blue colour of the sky is due to

13. The time taken to reach the Sunlight up to the surface of Earth is approximately

14. The visible range of solar radiation is

15. A cut diamond shines brilliantly due to

16. Consider the following statements.
1. Light of longer wavelength is scattered much more than the light of shorter wavelength.
2. The speed of visible light in water is 0.95 times the speed in vacuum.
3. Radio waves are produced by rapidly oscillating electrical currents.
4. To detect the overspeeding vehicles, police use the Doppler effect of reflected short radio waves. Which of these statements are correct?

17. The number of images of an object placed between two parallel mirrors is

18. An air bubble in water will act like a

19. Light is made of seven colours. What is the method of separating the colours?

20. Find out the odd colour from the following options.

21. Which type of image of an object is formed by eye lens of the retina?

22. Photosynthesis using the invisible part of the Sunlight is done by some

23. The terminal colour bands of the rainbow are

24. The colour of light is determined by its

25. The colour of an opaque object is due to the colour it